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7c349ed090
560 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Kuniyuki Iwashima
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7c349ed090 |
af_unix: Remove scm_fp_dup() in unix_attach_fds().
When we passed fds, we used to bump each file's refcount twice
in scm_fp_copy() and scm_fp_dup() before linking the socket to
gc_inflight_list.
This is because we incremented the inflight count of the socket
and linked it to the list in advance before passing skb to the
destination socket.
Otherwise, the inflight socket could have been garbage-collected
in a small race window between linking the socket to the list and
queuing skb:
CPU 1 : sendmsg(X) w/ A's fd CPU 2 : close(A)
----- -----
/* Here A's refcount is 1, and inflight count is 0 */
bump A's refcount to 2 in scm_fp_copy()
bump A's inflight count to 1
link A to gc_inflight_list
decrement A's refcount to 1
/* A's refcount == inflight count, thus A could be GC candidate */
start GC
mark A as candidate
purge A's receive queue
queue skb w/ A's fd to X
/* A is queued, but all data has been lost */
After commit
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Eric Dumazet
|
1abe267f17 |
net: add sk_wake_async_rcu() helper
While looking at UDP receive performance, I saw sk_wake_async() was no longer inlined. This matters at least on AMD Zen1-4 platforms (see SRSO) This might be because rcu_read_lock() and rcu_read_unlock() are no longer nops in recent kernels ? Add sk_wake_async_rcu() variant, which must be called from contexts already holding rcu lock. As SOCK_FASYNC is deprecated in modern days, use unlikely() to give a hint to the compiler. sk_wake_async_rcu() is properly inlined from __udp_enqueue_schedule_skb() and sock_def_readable(). Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240328144032.1864988-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
|
4090fa373f |
af_unix: Replace garbage collection algorithm.
If we find a dead SCC during iteration, we call unix_collect_skb() to splice all skb in the SCC to the global sk_buff_head, hitlist. After iterating all SCC, we unlock unix_gc_lock and purge the queue. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-15-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
|
a15702d8b3 |
af_unix: Detect dead SCC.
When iterating SCC, we call unix_vertex_dead() for each vertex to check if the vertex is close()d and has no bridge to another SCC. If both conditions are true for every vertex in SCC, we can execute garbage collection for all skb in the SCC. The actual garbage collection is done in the following patch, replacing the old implementation. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-14-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
|
bfdb01283e |
af_unix: Assign a unique index to SCC.
The definition of the lowlink in Tarjan's algorithm is the smallest index of a vertex that is reachable with at most one back-edge in SCC. This is not useful for a cross-edge. If we start traversing from A in the following graph, the final lowlink of D is 3. The cross-edge here is one between D and C. A -> B -> D D = (4, 3) (index, lowlink) ^ | | C = (3, 1) | V | B = (2, 1) `--- C <--' A = (1, 1) This is because the lowlink of D is updated with the index of C. In the following patch, we detect a dead SCC by checking two conditions for each vertex. 1) vertex has no edge directed to another SCC (no bridge) 2) vertex's out_degree is the same as the refcount of its file If 1) is false, there is a receiver of all fds of the SCC and its ancestor SCC. To evaluate 1), we need to assign a unique index to each SCC and assign it to all vertices in the SCC. This patch changes the lowlink update logic for cross-edge so that in the example above, the lowlink of D is updated with the lowlink of C. A -> B -> D D = (4, 1) (index, lowlink) ^ | | C = (3, 1) | V | B = (2, 1) `--- C <--' A = (1, 1) Then, all vertices in the same SCC have the same lowlink, and we can quickly find the bridge connecting to different SCC if exists. However, it is no longer called lowlink, so we rename it to scc_index. (It's sometimes called lowpoint.) Also, we add a global variable to hold the last index used in DFS so that we do not reset the initial index in each DFS. This patch can be squashed to the SCC detection patch but is split deliberately for anyone wondering why lowlink is not used as used in the original Tarjan's algorithm and many reference implementations. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-13-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
|
ad081928a8 |
af_unix: Avoid Tarjan's algorithm if unnecessary.
Once a cyclic reference is formed, we need to run GC to check if there is dead SCC. However, we do not need to run Tarjan's algorithm if we know that the shape of the inflight graph has not been changed. If an edge is added/updated/deleted and the edge's successor is inflight, we set false to unix_graph_grouped, which means we need to re-classify SCC. Once we finalise SCC, we set true to unix_graph_grouped. While unix_graph_grouped is true, we can iterate the grouped SCC using vertex->scc_entry in unix_walk_scc_fast(). list_add() and list_for_each_entry_reverse() uses seem weird, but they are to keep the vertex order consistent and make writing test easier. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-12-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
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77e5593aeb |
af_unix: Skip GC if no cycle exists.
We do not need to run GC if there is no possible cyclic reference. We use unix_graph_maybe_cyclic to decide if we should run GC. If a fd of an AF_UNIX socket is passed to an already inflight AF_UNIX socket, they could form a cyclic reference. Then, we set true to unix_graph_maybe_cyclic and later run Tarjan's algorithm to group them into SCC. Once we run Tarjan's algorithm, we are 100% sure whether cyclic references exist or not. If there is no cycle, we set false to unix_graph_maybe_cyclic and can skip the entire garbage collection next time. When finalising SCC, we set true to unix_graph_maybe_cyclic if SCC consists of multiple vertices. Even if SCC is a single vertex, a cycle might exist as self-fd passing. Given the corner case is rare, we detect it by checking all edges of the vertex and set true to unix_graph_maybe_cyclic. With this change, __unix_gc() is just a spin_lock() dance in the normal usage. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-11-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
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ba31b4a4e1 |
af_unix: Save O(n) setup of Tarjan's algo.
Before starting Tarjan's algorithm, we need to mark all vertices as unvisited. We can save this O(n) setup by reserving two special indices (0, 1) and using two variables. The first time we link a vertex to unix_unvisited_vertices, we set unix_vertex_unvisited_index to index. During DFS, we can see that the index of unvisited vertices is the same as unix_vertex_unvisited_index. When we finalise SCC later, we set unix_vertex_grouped_index to each vertex's index. Then, we can know (i) that the vertex is on the stack if the index of a visited vertex is >= 2 and (ii) that it is not on the stack and belongs to a different SCC if the index is unix_vertex_grouped_index. After the whole algorithm, all indices of vertices are set as unix_vertex_grouped_index. Next time we start DFS, we know that all unvisited vertices have unix_vertex_grouped_index, and we can use unix_vertex_unvisited_index as the not-on-stack marker. To use the same variable in __unix_walk_scc(), we can swap unix_vertex_(grouped|unvisited)_index at the end of Tarjan's algorithm. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-10-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
|
dcf70df204 |
af_unix: Fix up unix_edge.successor for embryo socket.
To garbage collect inflight AF_UNIX sockets, we must define the
cyclic reference appropriately. This is a bit tricky if the loop
consists of embryo sockets.
Suppose that the fd of AF_UNIX socket A is passed to D and the fd B
to C and that C and D are embryo sockets of A and B, respectively.
It may appear that there are two separate graphs, A (-> D) and
B (-> C), but this is not correct.
A --. .-- B
X
C <-' `-> D
Now, D holds A's refcount, and C has B's refcount, so unix_release()
will never be called for A and B when we close() them. However, no
one can call close() for D and C to free skbs holding refcounts of A
and B because C/D is in A/B's receive queue, which should have been
purged by unix_release() for A and B.
So, here's another type of cyclic reference. When a fd of an AF_UNIX
socket is passed to an embryo socket, the reference is indirectly held
by its parent listening socket.
.-> A .-> B
| `- sk_receive_queue | `- sk_receive_queue
| `- skb | `- skb
| `- sk == C | `- sk == D
| `- sk_receive_queue | `- sk_receive_queue
| `- skb +---------' `- skb +-.
| |
`---------------------------------------------------------'
Technically, the graph must be denoted as A <-> B instead of A (-> D)
and B (-> C) to find such a cyclic reference without touching each
socket's receive queue.
.-> A --. .-- B <-.
| X | == A <-> B
`-- C <-' `-> D --'
We apply this fixup during GC by fetching the real successor by
unix_edge_successor().
When we call accept(), we clear unix_sock.listener under unix_gc_lock
not to confuse GC.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240325202425.60930-9-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Kuniyuki Iwashima
|
aed6ecef55 |
af_unix: Save listener for embryo socket.
This is a prep patch for the following change, where we need to fetch the listening socket from the successor embryo socket during GC. We add a new field to struct unix_sock to save a pointer to a listening socket. We set it when connect() creates a new socket, and clear it when accept() is called. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-8-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
|
3484f06317 |
af_unix: Detect Strongly Connected Components.
In the new GC, we use a simple graph algorithm, Tarjan's Strongly
Connected Components (SCC) algorithm, to find cyclic references.
The algorithm visits every vertex exactly once using depth-first
search (DFS).
DFS starts by pushing an input vertex to a stack and assigning it
a unique number. Two fields, index and lowlink, are initialised
with the number, but lowlink could be updated later during DFS.
If a vertex has an edge to an unvisited inflight vertex, we visit
it and do the same processing. So, we will have vertices in the
stack in the order they appear and number them consecutively in
the same order.
If a vertex has a back-edge to a visited vertex in the stack,
we update the predecessor's lowlink with the successor's index.
After iterating edges from the vertex, we check if its index
equals its lowlink.
If the lowlink is different from the index, it shows there was a
back-edge. Then, we go backtracking and propagate the lowlink to
its predecessor and resume the previous edge iteration from the
next edge.
If the lowlink is the same as the index, we pop vertices before
and including the vertex from the stack. Then, the set of vertices
is SCC, possibly forming a cycle. At the same time, we move the
vertices to unix_visited_vertices.
When we finish the algorithm, all vertices in each SCC will be
linked via unix_vertex.scc_entry.
Let's take an example. We have a graph including five inflight
vertices (F is not inflight):
A -> B -> C -> D -> E (-> F)
^ |
`---------'
Suppose that we start DFS from C. We will visit C, D, and B first
and initialise their index and lowlink. Then, the stack looks like
this:
> B = (3, 3) (index, lowlink)
D = (2, 2)
C = (1, 1)
When checking B's edge to C, we update B's lowlink with C's index
and propagate it to D.
B = (3, 1) (index, lowlink)
> D = (2, 1)
C = (1, 1)
Next, we visit E, which has no edge to an inflight vertex.
> E = (4, 4) (index, lowlink)
B = (3, 1)
D = (2, 1)
C = (1, 1)
When we leave from E, its index and lowlink are the same, so we
pop E from the stack as single-vertex SCC. Next, we leave from
B and D but do nothing because their lowlink are different from
their index.
B = (3, 1) (index, lowlink)
D = (2, 1)
> C = (1, 1)
Then, we leave from C, whose index and lowlink are the same, so
we pop B, D and C as SCC.
Last, we do DFS for the rest of vertices, A, which is also a
single-vertex SCC.
Finally, each unix_vertex.scc_entry is linked as follows:
A -. B -> C -> D E -.
^ | ^ | ^ |
`--' `---------' `--'
We use SCC later to decide whether we can garbage-collect the
sockets.
Note that we still cannot detect SCC properly if an edge points
to an embryo socket. The following two patches will sort it out.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240325202425.60930-7-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Kuniyuki Iwashima
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6ba76fd284 |
af_unix: Iterate all vertices by DFS.
The new GC will use a depth first search graph algorithm to find cyclic references. The algorithm visits every vertex exactly once. Here, we implement the DFS part without recursion so that no one can abuse it. unix_walk_scc() marks every vertex unvisited by initialising index as UNIX_VERTEX_INDEX_UNVISITED and iterates inflight vertices in unix_unvisited_vertices and call __unix_walk_scc() to start DFS from an arbitrary vertex. __unix_walk_scc() iterates all edges starting from the vertex and explores the neighbour vertices with DFS using edge_stack. After visiting all neighbours, __unix_walk_scc() moves the visited vertex to unix_visited_vertices so that unix_walk_scc() will not restart DFS from the visited vertex. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-6-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
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22c3c0c52d |
af_unix: Bulk update unix_tot_inflight/unix_inflight when queuing skb.
Currently, we track the number of inflight sockets in two variables. unix_tot_inflight is the total number of inflight AF_UNIX sockets on the host, and user->unix_inflight is the number of inflight fds per user. We update them one by one in unix_inflight(), which can be done once in batch. Also, sendmsg() could fail even after unix_inflight(), then we need to acquire unix_gc_lock only to decrement the counters. Let's bulk update the counters in unix_add_edges() and unix_del_edges(), which is called only for successfully passed fds. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-5-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
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42f298c06b |
af_unix: Link struct unix_edge when queuing skb.
Just before queuing skb with inflight fds, we call scm_stat_add(),
which is a good place to set up the preallocated struct unix_vertex
and struct unix_edge in UNIXCB(skb).fp.
Then, we call unix_add_edges() and construct the directed graph
as follows:
1. Set the inflight socket's unix_sock to unix_edge.predecessor.
2. Set the receiver's unix_sock to unix_edge.successor.
3. Set the preallocated vertex to inflight socket's unix_sock.vertex.
4. Link inflight socket's unix_vertex.entry to unix_unvisited_vertices.
5. Link unix_edge.vertex_entry to the inflight socket's unix_vertex.edges.
Let's say we pass the fd of AF_UNIX socket A to B and the fd of B
to C. The graph looks like this:
+-------------------------+
| unix_unvisited_vertices | <-------------------------.
+-------------------------+ |
+ |
| +--------------+ +--------------+ | +--------------+
| | unix_sock A | <---. .---> | unix_sock B | <-|-. .---> | unix_sock C |
| +--------------+ | | +--------------+ | | | +--------------+
| .-+ | vertex | | | .-+ | vertex | | | | | vertex |
| | +--------------+ | | | +--------------+ | | | +--------------+
| | | | | | | |
| | +--------------+ | | | +--------------+ | | |
| '-> | unix_vertex | | | '-> | unix_vertex | | | |
| +--------------+ | | +--------------+ | | |
`---> | entry | +---------> | entry | +-' | |
|--------------| | | |--------------| | |
| edges | <-. | | | edges | <-. | |
+--------------+ | | | +--------------+ | | |
| | | | | |
.----------------------' | | .----------------------' | |
| | | | | |
| +--------------+ | | | +--------------+ | |
| | unix_edge | | | | | unix_edge | | |
| +--------------+ | | | +--------------+ | |
`-> | vertex_entry | | | `-> | vertex_entry | | |
|--------------| | | |--------------| | |
| predecessor | +---' | | predecessor | +---' |
|--------------| | |--------------| |
| successor | +-----' | successor | +-----'
+--------------+ +--------------+
Henceforth, we denote such a graph as A -> B (-> C).
Now, we can express all inflight fd graphs that do not contain
embryo sockets. We will support the particular case later.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240325202425.60930-4-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Kuniyuki Iwashima
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29b64e3540 |
af_unix: Allocate struct unix_edge for each inflight AF_UNIX fd.
As with the previous patch, we preallocate to skb's scm_fp_list an array of struct unix_edge in the number of inflight AF_UNIX fds. There we just preallocate memory and do not use immediately because sendmsg() could fail after this point. The actual use will be in the next patch. When we queue skb with inflight edges, we will set the inflight socket's unix_sock as unix_edge->predecessor and the receiver's unix_sock as successor, and then we will link the edge to the inflight socket's unix_vertex.edges. Note that we set NULL to cloned scm_fp_list.edges in scm_fp_dup() so that MSG_PEEK does not change the shape of the directed graph. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Kuniyuki Iwashima
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1fbfdfaa59 |
af_unix: Allocate struct unix_vertex for each inflight AF_UNIX fd.
We will replace the garbage collection algorithm for AF_UNIX, where we will consider each inflight AF_UNIX socket as a vertex and its file descriptor as an edge in a directed graph. This patch introduces a new struct unix_vertex representing a vertex in the graph and adds its pointer to struct unix_sock. When we send a fd using the SCM_RIGHTS message, we allocate struct scm_fp_list to struct scm_cookie in scm_fp_copy(). Then, we bump each refcount of the inflight fds' struct file and save them in scm_fp_list.fp. After that, unix_attach_fds() inexplicably clones scm_fp_list of scm_cookie and sets it to skb. (We will remove this part after replacing GC.) Here, we add a new function call in unix_attach_fds() to preallocate struct unix_vertex per inflight AF_UNIX fd and link each vertex to skb's scm_fp_list.vertices. When sendmsg() succeeds later, if the socket of the inflight fd is still not inflight yet, we will set the preallocated vertex to struct unix_sock.vertex and link it to a global list unix_unvisited_vertices under spin_lock(&unix_gc_lock). If the socket is already inflight, we free the preallocated vertex. This is to avoid taking the lock unnecessarily when sendmsg() could fail later. In the following patch, we will similarly allocate another struct per edge, which will finally be linked to the inflight socket's unix_vertex.edges. And then, we will count the number of edges as unix_vertex.out_degree. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Jakub Kicinski
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fecc51559a |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: net/ipv4/udp.c |
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Kuniyuki Iwashima
|
aa82ac51d6 |
af_unix: Drop oob_skb ref before purging queue in GC.
syzbot reported another task hung in __unix_gc(). [0]
The current while loop assumes that all of the left candidates
have oob_skb and calling kfree_skb(oob_skb) releases the remaining
candidates.
However, I missed a case that oob_skb has self-referencing fd and
another fd and the latter sk is placed before the former in the
candidate list. Then, the while loop never proceeds, resulting
the task hung.
__unix_gc() has the same loop just before purging the collected skb,
so we can call kfree_skb(oob_skb) there and let __skb_queue_purge()
release all inflight sockets.
[0]:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 2784 Comm: kworker/u4:8 Not tainted 6.8.0-rc4-syzkaller-01028-g71b605d32017 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Workqueue: events_unbound __unix_gc
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200
Code: 89 fb e8 23 00 00 00 48 8b 3d 84 f5 1a 0c 48 89 de 5b e9 43 26 57 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0d 90 52 70 7e 65 8b 15 91 52 70
RSP: 0018:ffffc9000a17fa78 EFLAGS: 00000287
RAX: ffffffff8a0a6108 RBX: ffff88802b6c2640 RCX: ffff88802c0b3b80
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffffc9000a17fbf0 R08: ffffffff89383f1d R09: 1ffff1100ee5ff84
R10: dffffc0000000000 R11: ffffed100ee5ff85 R12: 1ffff110056d84ee
R13: ffffc9000a17fae0 R14: 0000000000000000 R15: ffffffff8f47b840
FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffef5687ff8 CR3: 0000000029b34000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
__unix_gc+0xe69/0xf40 net/unix/garbage.c:343
process_one_work kernel/workqueue.c:2633 [inline]
process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706
worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787
kthread+0x2ef/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242
</TASK>
Reported-and-tested-by: syzbot+ecab4d36f920c3574bf9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=ecab4d36f920c3574bf9
Fixes:
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Eric Dumazet
|
56667da739 |
net: implement lockless setsockopt(SO_PEEK_OFF)
syzbot reported a lockdep violation [1] involving af_unix
support of SO_PEEK_OFF.
Since SO_PEEK_OFF is inherently not thread safe (it uses a per-socket
sk_peek_off field), there is really no point to enforce a pointless
thread safety in the kernel.
After this patch :
- setsockopt(SO_PEEK_OFF) no longer acquires the socket lock.
- skb_consume_udp() no longer has to acquire the socket lock.
- af_unix no longer needs a special version of sk_set_peek_off(),
because it does not lock u->iolock anymore.
As a followup, we could replace prot->set_peek_off to be a boolean
and avoid an indirect call, since we always use sk_set_peek_off().
[1]
WARNING: possible circular locking dependency detected
6.8.0-rc4-syzkaller-00267-g0f1dd5e91e2b #0 Not tainted
syz-executor.2/30025 is trying to acquire lock:
ffff8880765e7d80 (&u->iolock){+.+.}-{3:3}, at: unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789
but task is already holding lock:
ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline]
ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1060 [inline]
ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sk_setsockopt+0xe52/0x3360 net/core/sock.c:1193
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (sk_lock-AF_UNIX){+.+.}-{0:0}:
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
lock_sock_nested+0x48/0x100 net/core/sock.c:3524
lock_sock include/net/sock.h:1691 [inline]
__unix_dgram_recvmsg+0x1275/0x12c0 net/unix/af_unix.c:2415
sock_recvmsg_nosec+0x18e/0x1d0 net/socket.c:1046
____sys_recvmsg+0x3c0/0x470 net/socket.c:2801
___sys_recvmsg net/socket.c:2845 [inline]
do_recvmmsg+0x474/0xae0 net/socket.c:2939
__sys_recvmmsg net/socket.c:3018 [inline]
__do_sys_recvmmsg net/socket.c:3041 [inline]
__se_sys_recvmmsg net/socket.c:3034 [inline]
__x64_sys_recvmmsg+0x199/0x250 net/socket.c:3034
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77
-> #0 (&u->iolock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869
__lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789
sk_setsockopt+0x207e/0x3360
do_sock_setsockopt+0x2fb/0x720 net/socket.c:2307
__sys_setsockopt+0x1ad/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(sk_lock-AF_UNIX);
lock(&u->iolock);
lock(sk_lock-AF_UNIX);
lock(&u->iolock);
*** DEADLOCK ***
1 lock held by syz-executor.2/30025:
#0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline]
#0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1060 [inline]
#0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sk_setsockopt+0xe52/0x3360 net/core/sock.c:1193
stack backtrace:
CPU: 0 PID: 30025 Comm: syz-executor.2 Not tainted 6.8.0-rc4-syzkaller-00267-g0f1dd5e91e2b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869
__lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789
sk_setsockopt+0x207e/0x3360
do_sock_setsockopt+0x2fb/0x720 net/socket.c:2307
__sys_setsockopt+0x1ad/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f78a1c7dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f78a0fde0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f78a1dac050 RCX: 00007f78a1c7dda9
RDX: 000000000000002a RSI: 0000000000000001 RDI: 0000000000000006
RBP: 00007f78a1cca47a R08: 0000000000000004 R09: 0000000000000000
R10: 0000000020000180 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f78a1dac050 R15: 00007ffe5cd81ae8
Fixes:
|
||
|
Jakub Kicinski
|
73be9a3aab |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: net/core/dev.c |
||
|
Kuniyuki Iwashima
|
25236c91b5 |
af_unix: Fix task hung while purging oob_skb in GC.
syzbot reported a task hung; at the same time, GC was looping infinitely
in list_for_each_entry_safe() for OOB skb. [0]
syzbot demonstrated that the list_for_each_entry_safe() was not actually
safe in this case.
A single skb could have references for multiple sockets. If we free such
a skb in the list_for_each_entry_safe(), the current and next sockets could
be unlinked in a single iteration.
unix_notinflight() uses list_del_init() to unlink the socket, so the
prefetched next socket forms a loop itself and list_for_each_entry_safe()
never stops.
Here, we must use while() and make sure we always fetch the first socket.
[0]:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5065 Comm: syz-executor236 Not tainted 6.8.0-rc3-syzkaller-00136-g1f719a2f3fa6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x60 kernel/kcov.c:207
Code: cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 48 8b 14 25 40 c2 03 00 <65> 8b 05 b4 7c 78 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74
RSP: 0018:ffffc900033efa58 EFLAGS: 00000283
RAX: ffff88807b077800 RBX: ffff88807b077800 RCX: 1ffffffff27b1189
RDX: ffff88802a5a3b80 RSI: ffffffff8968488d RDI: ffff88807b077f70
RBP: ffffc900033efbb0 R08: 0000000000000001 R09: fffffbfff27a900c
R10: ffffffff93d48067 R11: ffffffff8ae000eb R12: ffff88807b077800
R13: dffffc0000000000 R14: ffff88807b077e40 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564f4fc1e3a8 CR3: 000000000d57a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
unix_gc+0x563/0x13b0 net/unix/garbage.c:319
unix_release_sock+0xa93/0xf80 net/unix/af_unix.c:683
unix_release+0x91/0xf0 net/unix/af_unix.c:1064
__sock_release+0xb0/0x270 net/socket.c:659
sock_close+0x1c/0x30 net/socket.c:1421
__fput+0x270/0xb80 fs/file_table.c:376
task_work_run+0x14f/0x250 kernel/task_work.c:180
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0xa8a/0x2ad0 kernel/exit.c:871
do_group_exit+0xd4/0x2a0 kernel/exit.c:1020
__do_sys_exit_group kernel/exit.c:1031 [inline]
__se_sys_exit_group kernel/exit.c:1029 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1029
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f9d6cbdac09
Code: Unable to access opcode bytes at 0x7f9d6cbdabdf.
RSP: 002b:00007fff5952feb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9d6cbdac09
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 00007f9d6cc552b0 R08: ffffffffffffffb8 R09: 0000000000000006
R10: 0000000000000006 R11: 0000000000000246 R12: 00007f9d6cc552b0
R13: 0000000000000000 R14: 00007f9d6cc55d00 R15: 00007f9d6cbabe70
</TASK>
Reported-by: syzbot+4fa4a2d1f5a5ee06f006@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=4fa4a2d1f5a5ee06f006
Fixes:
|
||
|
Jakub Kicinski
|
3be042cf46 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: drivers/net/ethernet/stmicro/stmmac/common.h |
||
|
Kuniyuki Iwashima
|
1279f9d9de |
af_unix: Call kfree_skb() for dead unix_(sk)->oob_skb in GC.
syzbot reported a warning [0] in __unix_gc() with a repro, which
creates a socketpair and sends one socket's fd to itself using the
peer.
socketpair(AF_UNIX, SOCK_STREAM, 0, [3, 4]) = 0
sendmsg(4, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\360", iov_len=1}],
msg_iovlen=1, msg_control=[{cmsg_len=20, cmsg_level=SOL_SOCKET,
cmsg_type=SCM_RIGHTS, cmsg_data=[3]}],
msg_controllen=24, msg_flags=0}, MSG_OOB|MSG_PROBE|MSG_DONTWAIT|MSG_ZEROCOPY) = 1
This forms a self-cyclic reference that GC should finally untangle
but does not due to lack of MSG_OOB handling, resulting in memory
leak.
Recently, commit
|
||
|
Jakub Kicinski
|
cf244463a2 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
|
Eric Dumazet
|
4d322dce82 |
af_unix: fix lockdep positive in sk_diag_dump_icons()
syzbot reported a lockdep splat [1].
Blamed commit hinted about the possible lockdep
violation, and code used unix_state_lock_nested()
in an attempt to silence lockdep.
It is not sufficient, because unix_state_lock_nested()
is already used from unix_state_double_lock().
We need to use a separate subclass.
This patch adds a distinct enumeration to make things
more explicit.
Also use swap() in unix_state_double_lock() as a clean up.
v2: add a missing inline keyword to unix_state_lock_nested()
[1]
WARNING: possible circular locking dependency detected
6.8.0-rc1-syzkaller-00356-g8a696a29c690 #0 Not tainted
syz-executor.1/2542 is trying to acquire lock:
ffff88808b5df9e8 (rlock-AF_UNIX){+.+.}-{2:2}, at: skb_queue_tail+0x36/0x120 net/core/skbuff.c:3863
but task is already holding lock:
ffff88808b5dfe70 (&u->lock/1){+.+.}-{2:2}, at: unix_dgram_sendmsg+0xfc7/0x2200 net/unix/af_unix.c:2089
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&u->lock/1){+.+.}-{2:2}:
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
_raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
sk_diag_dump_icons net/unix/diag.c:87 [inline]
sk_diag_fill+0x6ea/0xfe0 net/unix/diag.c:157
sk_diag_dump net/unix/diag.c:196 [inline]
unix_diag_dump+0x3e9/0x630 net/unix/diag.c:220
netlink_dump+0x5c1/0xcd0 net/netlink/af_netlink.c:2264
__netlink_dump_start+0x5d7/0x780 net/netlink/af_netlink.c:2370
netlink_dump_start include/linux/netlink.h:338 [inline]
unix_diag_handler_dump+0x1c3/0x8f0 net/unix/diag.c:319
sock_diag_rcv_msg+0xe3/0x400
netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2543
sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:280
netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
netlink_unicast+0x7e6/0x980 net/netlink/af_netlink.c:1367
netlink_sendmsg+0xa37/0xd70 net/netlink/af_netlink.c:1908
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
sock_write_iter+0x39a/0x520 net/socket.c:1160
call_write_iter include/linux/fs.h:2085 [inline]
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0xa74/0xca0 fs/read_write.c:590
ksys_write+0x1a0/0x2c0 fs/read_write.c:643
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
-> #0 (rlock-AF_UNIX){+.+.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x1909/0x5ab0 kernel/locking/lockdep.c:3869
__lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
skb_queue_tail+0x36/0x120 net/core/skbuff.c:3863
unix_dgram_sendmsg+0x15d9/0x2200 net/unix/af_unix.c:2112
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0x592/0x890 net/socket.c:2584
___sys_sendmsg net/socket.c:2638 [inline]
__sys_sendmmsg+0x3b2/0x730 net/socket.c:2724
__do_sys_sendmmsg net/socket.c:2753 [inline]
__se_sys_sendmmsg net/socket.c:2750 [inline]
__x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2750
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&u->lock/1);
lock(rlock-AF_UNIX);
lock(&u->lock/1);
lock(rlock-AF_UNIX);
*** DEADLOCK ***
1 lock held by syz-executor.1/2542:
#0: ffff88808b5dfe70 (&u->lock/1){+.+.}-{2:2}, at: unix_dgram_sendmsg+0xfc7/0x2200 net/unix/af_unix.c:2089
stack backtrace:
CPU: 1 PID: 2542 Comm: syz-executor.1 Not tainted 6.8.0-rc1-syzkaller-00356-g8a696a29c690 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
check_noncircular+0x366/0x490 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x1909/0x5ab0 kernel/locking/lockdep.c:3869
__lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
skb_queue_tail+0x36/0x120 net/core/skbuff.c:3863
unix_dgram_sendmsg+0x15d9/0x2200 net/unix/af_unix.c:2112
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0x592/0x890 net/socket.c:2584
___sys_sendmsg net/socket.c:2638 [inline]
__sys_sendmmsg+0x3b2/0x730 net/socket.c:2724
__do_sys_sendmmsg net/socket.c:2753 [inline]
__se_sys_sendmmsg net/socket.c:2750 [inline]
__x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2750
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f26d887cda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f26d95a60c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f26d89abf80 RCX: 00007f26d887cda9
RDX: 000000000000003e RSI: 00000000200bd000 RDI: 0000000000000004
RBP: 00007f26d88c947a R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000008c0 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f26d89abf80 R15: 00007ffcfe081a68
Fixes:
|
||
|
Kuniyuki Iwashima
|
99a7a5b994 |
af_unix: Remove CONFIG_UNIX_SCM.
Originally, the code related to garbage collection was all in garbage.c. Commit |
||
|
Kuniyuki Iwashima
|
11498715f2 |
af_unix: Remove io_uring code for GC.
Since commit |
||
|
Kuniyuki Iwashima
|
d0f6dc2634 |
af_unix: Replace BUG_ON() with WARN_ON_ONCE().
This is a prep patch for the last patch in this series so that checkpatch will not warn about BUG_ON(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20240129190435.57228-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
|
Kuniyuki Iwashima
|
d9f21b3613 |
af_unix: Try to run GC async.
If more than 16000 inflight AF_UNIX sockets exist and the garbage
collector is not running, unix_(dgram|stream)_sendmsg() call unix_gc().
Also, they wait for unix_gc() to complete.
In unix_gc(), all inflight AF_UNIX sockets are traversed at least once,
and more if they are the GC candidate. Thus, sendmsg() significantly
slows down with too many inflight AF_UNIX sockets.
However, if a process sends data with no AF_UNIX FD, the sendmsg() call
does not need to wait for GC. After this change, only the process that
meets the condition below will be blocked under such a situation.
1) cmsg contains AF_UNIX socket
2) more than 32 AF_UNIX sent by the same user are still inflight
Note that even a sendmsg() call that does not meet the condition but has
AF_UNIX FD will be blocked later in unix_scm_to_skb() by the spinlock,
but we allow that as a bonus for sane users.
The results below are the time spent in unix_dgram_sendmsg() sending 1
byte of data with no FD 4096 times on a host where 32K inflight AF_UNIX
sockets exist.
Without series: the sane sendmsg() needs to wait gc unreasonably.
$ sudo /usr/share/bcc/tools/funclatency -p 11165 unix_dgram_sendmsg
Tracing 1 functions for "unix_dgram_sendmsg"... Hit Ctrl-C to end.
^C
nsecs : count distribution
[...]
524288 -> 1048575 : 0 | |
1048576 -> 2097151 : 3881 |****************************************|
2097152 -> 4194303 : 214 |** |
4194304 -> 8388607 : 1 | |
avg = 1825567 nsecs, total: 7477526027 nsecs, count: 4096
With series: the sane sendmsg() can finish much faster.
$ sudo /usr/share/bcc/tools/funclatency -p 8702 unix_dgram_sendmsg
Tracing 1 functions for "unix_dgram_sendmsg"... Hit Ctrl-C to end.
^C
nsecs : count distribution
[...]
128 -> 255 : 0 | |
256 -> 511 : 4092 |****************************************|
512 -> 1023 : 2 | |
1024 -> 2047 : 0 | |
2048 -> 4095 : 0 | |
4096 -> 8191 : 1 | |
8192 -> 16383 : 1 | |
avg = 410 nsecs, total: 1680510 nsecs, count: 4096
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240123170856.41348-6-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
||
|
Kuniyuki Iwashima
|
8b90a9f819 |
af_unix: Run GC on only one CPU.
If more than 16000 inflight AF_UNIX sockets exist and the garbage
collector is not running, unix_(dgram|stream)_sendmsg() call unix_gc().
Also, they wait for unix_gc() to complete.
In unix_gc(), all inflight AF_UNIX sockets are traversed at least once,
and more if they are the GC candidate. Thus, sendmsg() significantly
slows down with too many inflight AF_UNIX sockets.
There is a small window to invoke multiple unix_gc() instances, which
will then be blocked by the same spinlock except for one.
Let's convert unix_gc() to use struct work so that it will not consume
CPUs unnecessarily.
Note WRITE_ONCE(gc_in_progress, true) is moved before running GC.
If we leave the WRITE_ONCE() as is and use the following test to
call flush_work(), a process might not call it.
CPU 0 CPU 1
--- ---
start work and call __unix_gc()
if (work_pending(&unix_gc_work) || <-- false
READ_ONCE(gc_in_progress)) <-- false
flush_work(); <-- missed!
WRITE_ONCE(gc_in_progress, true)
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240123170856.41348-5-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
||
|
Kuniyuki Iwashima
|
5b17307bd0 |
af_unix: Return struct unix_sock from unix_get_socket().
Currently, unix_get_socket() returns struct sock, but after calling it, we always cast it to unix_sk(). Let's return struct unix_sock from unix_get_socket(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20240123170856.41348-4-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
|
Kuniyuki Iwashima
|
97af84a6bb |
af_unix: Do not use atomic ops for unix_sk(sk)->inflight.
When touching unix_sk(sk)->inflight, we are always under spin_lock(&unix_gc_lock). Let's convert unix_sk(sk)->inflight to the normal unsigned long. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20240123170856.41348-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
|
Kuniyuki Iwashima
|
31e0320711 |
af_unix: Annotate data-race of gc_in_progress in wait_for_unix_gc().
gc_in_progress is changed under spin_lock(&unix_gc_lock),
but wait_for_unix_gc() reads it locklessly.
Let's use READ_ONCE().
Fixes:
|
||
|
Eric Dumazet
|
114b4bb1cc |
sock_diag: add module pointer to "struct sock_diag_handler"
Following patch is going to use RCU instead of sock_diag_table_mutex acquisition. This patch is a preparation, no change of behavior yet. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> |
||
|
Linus Torvalds
|
4c72e2b8c4 |
for-6.8/io_uring-2024-01-08
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Merge tag 'for-6.8/io_uring-2024-01-08' of git://git.kernel.dk/linux
Pull io_uring updates from Jens Axboe:
"Mostly just come fixes and cleanups, but one feature as well. In
detail:
- Harden the check for handling IOPOLL based on return (Pavel)
- Various minor optimizations (Pavel)
- Drop remnants of SCM_RIGHTS fd passing support, now that it's no
longer supported since 6.7 (me)
- Fix for a case where bytes_done wasn't initialized properly on a
failure condition for read/write requests (me)
- Move the register related code to a separate file (me)
- Add support for returning the provided ring buffer head (me)
- Add support for adding a direct descriptor to the normal file table
(me, Christian Brauner)
- Fix for ensuring pending task_work for a ring with DEFER_TASKRUN is
run even if we timeout waiting (me)"
* tag 'for-6.8/io_uring-2024-01-08' of git://git.kernel.dk/linux:
io_uring: ensure local task_work is run on wait timeout
io_uring/kbuf: add method for returning provided buffer ring head
io_uring/rw: ensure io->bytes_done is always initialized
io_uring: drop any code related to SCM_RIGHTS
io_uring/unix: drop usage of io_uring socket
io_uring/register: move io_uring_register(2) related code to register.c
io_uring/openclose: add support for IORING_OP_FIXED_FD_INSTALL
io_uring/cmd: inline io_uring_cmd_get_task
io_uring/cmd: inline io_uring_cmd_do_in_task_lazy
io_uring: split out cmd api into a separate header
io_uring: optimise ltimeout for inline execution
io_uring: don't check iopoll if request completes
|
||
|
John Fastabend
|
16b2f26498 |
bpf: sockmap, fix proto update hook to avoid dup calls
When sockets are added to a sockmap or sockhash we allocate and init a
psock. Then update the proto ops with sock_map_init_proto the flow is
sock_hash_update_common
sock_map_link
psock = sock_map_psock_get_checked() <-returns existing psock
sock_map_init_proto(sk, psock) <- updates sk_proto
If the socket is already in a map this results in the sock_map_init_proto
being called multiple times on the same socket. We do this because when
a socket is added to multiple maps this might result in a new set of BPF
programs being attached to the socket requiring an updated ops struct.
This creates a rule where it must be safe to call psock_update_sk_prot
multiple times. When we added a fix for UAF through unix sockets in patch
4dd9a38a753fc we broke this rule by adding a sock_hold in that path
to ensure the sock is not released. The result is if a af_unix stream sock
is placed in multiple maps it results in a memory leak because we call
sock_hold multiple times with only a single sock_put on it.
Fixes:
|
||
|
Jens Axboe
|
a4104821ad |
io_uring/unix: drop usage of io_uring socket
Since we no longer allow sending io_uring fds over SCM_RIGHTS, move to using io_is_uring_fops() to detect whether this is a io_uring fd or not. With that done, kill off io_uring_get_socket() as nobody calls it anymore. This is in preparation to yanking out the rest of the core related to unix gc with io_uring. Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
|
John Fastabend
|
8866730aed |
bpf, sockmap: af_unix stream sockets need to hold ref for pair sock
AF_UNIX stream sockets are a paired socket. So sending on one of the pairs
will lookup the paired socket as part of the send operation. It is possible
however to put just one of the pairs in a BPF map. This currently increments
the refcnt on the sock in the sockmap to ensure it is not free'd by the
stack before sockmap cleans up its state and stops any skbs being sent/recv'd
to that socket.
But we missed a case. If the peer socket is closed it will be free'd by the
stack. However, the paired socket can still be referenced from BPF sockmap
side because we hold a reference there. Then if we are sending traffic through
BPF sockmap to that socket it will try to dereference the free'd pair in its
send logic creating a use after free. And following splat:
[59.900375] BUG: KASAN: slab-use-after-free in sk_wake_async+0x31/0x1b0
[59.901211] Read of size 8 at addr ffff88811acbf060 by task kworker/1:2/954
[...]
[59.905468] Call Trace:
[59.905787] <TASK>
[59.906066] dump_stack_lvl+0x130/0x1d0
[59.908877] print_report+0x16f/0x740
[59.910629] kasan_report+0x118/0x160
[59.912576] sk_wake_async+0x31/0x1b0
[59.913554] sock_def_readable+0x156/0x2a0
[59.914060] unix_stream_sendmsg+0x3f9/0x12a0
[59.916398] sock_sendmsg+0x20e/0x250
[59.916854] skb_send_sock+0x236/0xac0
[59.920527] sk_psock_backlog+0x287/0xaa0
To fix let BPF sockmap hold a refcnt on both the socket in the sockmap and its
paired socket. It wasn't obvious how to contain the fix to bpf_unix logic. The
primarily problem with keeping this logic in bpf_unix was: In the sock close()
we could handle the deref by having a close handler. But, when we are destroying
the psock through a map delete operation we wouldn't have gotten any signal
thorugh the proto struct other than it being replaced. If we do the deref from
the proto replace its too early because we need to deref the sk_pair after the
backlog worker has been stopped.
Given all this it seems best to just cache it at the end of the psock and eat 8B
for the af_unix and vsock users. Notice dgram sockets are OK because they handle
locking already.
Fixes:
|
||
|
Jakub Kicinski
|
938dbead34 |
net: fill in MODULE_DESCRIPTION()s for SOCK_DIAG modules
W=1 builds now warn if module is built without a MODULE_DESCRIPTION(). Add descriptions to all the sock diag modules in one fell swoop. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
|
Eric Dumazet
|
4b7b492615 |
af_unix: fix use-after-free in unix_stream_read_actor()
syzbot reported the following crash [1]
After releasing unix socket lock, u->oob_skb can be changed
by another thread. We must temporarily increase skb refcount
to make sure this other thread will not free the skb under us.
[1]
BUG: KASAN: slab-use-after-free in unix_stream_read_actor+0xa7/0xc0 net/unix/af_unix.c:2866
Read of size 4 at addr ffff88801f3b9cc4 by task syz-executor107/5297
CPU: 1 PID: 5297 Comm: syz-executor107 Not tainted 6.6.0-syzkaller-15910-gb8e3a87a627b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0xc4/0x620 mm/kasan/report.c:475
kasan_report+0xda/0x110 mm/kasan/report.c:588
unix_stream_read_actor+0xa7/0xc0 net/unix/af_unix.c:2866
unix_stream_recv_urg net/unix/af_unix.c:2587 [inline]
unix_stream_read_generic+0x19a5/0x2480 net/unix/af_unix.c:2666
unix_stream_recvmsg+0x189/0x1b0 net/unix/af_unix.c:2903
sock_recvmsg_nosec net/socket.c:1044 [inline]
sock_recvmsg+0xe2/0x170 net/socket.c:1066
____sys_recvmsg+0x21f/0x5c0 net/socket.c:2803
___sys_recvmsg+0x115/0x1a0 net/socket.c:2845
__sys_recvmsg+0x114/0x1e0 net/socket.c:2875
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fc67492c559
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc6748ab228 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 000000000000001c RCX: 00007fc67492c559
RDX: 0000000040010083 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00007fc6749b6348 R08: 00007fc6748ab6c0 R09: 00007fc6748ab6c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc6749b6340
R13: 00007fc6749b634c R14: 00007ffe9fac52a0 R15: 00007ffe9fac5388
</TASK>
Allocated by task 5295:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
__kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook mm/slab.h:763 [inline]
slab_alloc_node mm/slub.c:3478 [inline]
kmem_cache_alloc_node+0x180/0x3c0 mm/slub.c:3523
__alloc_skb+0x287/0x330 net/core/skbuff.c:641
alloc_skb include/linux/skbuff.h:1286 [inline]
alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331
sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780
sock_alloc_send_skb include/net/sock.h:1884 [inline]
queue_oob net/unix/af_unix.c:2147 [inline]
unix_stream_sendmsg+0xb5f/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
Freed by task 5295:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522
____kasan_slab_free mm/kasan/common.c:236 [inline]
____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1800 [inline]
slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826
slab_free mm/slub.c:3809 [inline]
kmem_cache_free+0xf8/0x340 mm/slub.c:3831
kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:1015
__kfree_skb net/core/skbuff.c:1073 [inline]
consume_skb net/core/skbuff.c:1288 [inline]
consume_skb+0xdf/0x170 net/core/skbuff.c:1282
queue_oob net/unix/af_unix.c:2178 [inline]
unix_stream_sendmsg+0xd49/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
The buggy address belongs to the object at ffff88801f3b9c80
which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 68 bytes inside of
freed 240-byte region [ffff88801f3b9c80, ffff88801f3b9d70)
The buggy address belongs to the physical page:
page:ffffea00007cee40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f3b9
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888142a60640 dead000000000122 0000000000000000
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5299, tgid 5283 (syz-executor107), ts 103803840339, free_ts 103600093431
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1537
prep_new_page mm/page_alloc.c:1544 [inline]
get_page_from_freelist+0xa25/0x36c0 mm/page_alloc.c:3312
__alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4568
alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133
alloc_slab_page mm/slub.c:1870 [inline]
allocate_slab+0x251/0x380 mm/slub.c:2017
new_slab mm/slub.c:2070 [inline]
___slab_alloc+0x8c7/0x1580 mm/slub.c:3223
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322
__slab_alloc_node mm/slub.c:3375 [inline]
slab_alloc_node mm/slub.c:3468 [inline]
kmem_cache_alloc_node+0x132/0x3c0 mm/slub.c:3523
__alloc_skb+0x287/0x330 net/core/skbuff.c:641
alloc_skb include/linux/skbuff.h:1286 [inline]
alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331
sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780
sock_alloc_send_skb include/net/sock.h:1884 [inline]
queue_oob net/unix/af_unix.c:2147 [inline]
unix_stream_sendmsg+0xb5f/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1137 [inline]
free_unref_page_prepare+0x4f8/0xa90 mm/page_alloc.c:2347
free_unref_page+0x33/0x3b0 mm/page_alloc.c:2487
__unfreeze_partials+0x21d/0x240 mm/slub.c:2655
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook mm/slab.h:763 [inline]
slab_alloc_node mm/slub.c:3478 [inline]
slab_alloc mm/slub.c:3486 [inline]
__kmem_cache_alloc_lru mm/slub.c:3493 [inline]
kmem_cache_alloc+0x15d/0x380 mm/slub.c:3502
vm_area_dup+0x21/0x2f0 kernel/fork.c:500
__split_vma+0x17d/0x1070 mm/mmap.c:2365
split_vma mm/mmap.c:2437 [inline]
vma_modify+0x25d/0x450 mm/mmap.c:2472
vma_modify_flags include/linux/mm.h:3271 [inline]
mprotect_fixup+0x228/0xc80 mm/mprotect.c:635
do_mprotect_pkey+0x852/0xd60 mm/mprotect.c:809
__do_sys_mprotect mm/mprotect.c:830 [inline]
__se_sys_mprotect mm/mprotect.c:827 [inline]
__x64_sys_mprotect+0x78/0xb0 mm/mprotect.c:827
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
Memory state around the buggy address:
ffff88801f3b9b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88801f3b9c00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
>ffff88801f3b9c80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88801f3b9d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
ffff88801f3b9d80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
Fixes:
|
||
|
Kuniyuki Iwashima
|
3a04927f8d |
af_unix: Remove module remnants.
Since commit
|
||
|
Daan De Meyer
|
859051dd16 |
bpf: Implement cgroup sockaddr hooks for unix sockets
These hooks allows intercepting connect(), getsockname(), getpeername(), sendmsg() and recvmsg() for unix sockets. The unix socket hooks get write access to the address length because the address length is not fixed when dealing with unix sockets and needs to be modified when a unix socket address is modified by the hook. Because abstract socket unix addresses start with a NUL byte, we cannot recalculate the socket address in kernelspace after running the hook by calculating the length of the unix socket path using strlen(). These hooks can be used when users want to multiplex syscall to a single unix socket to multiple different processes behind the scenes by redirecting the connect() and other syscalls to process specific sockets. We do not implement support for intercepting bind() because when using bind() with unix sockets with a pathname address, this creates an inode in the filesystem which must be cleaned up. If we rewrite the address, the user might try to clean up the wrong file, leaking the socket in the filesystem where it is never cleaned up. Until we figure out a solution for this (and a use case for intercepting bind()), we opt to not allow rewriting the sockaddr in bind() calls. We also implement recvmsg() support for connected streams so that after a connect() that is modified by a sockaddr hook, any corresponding recmvsg() on the connected socket can also be modified to make the connected program think it is connected to the "intended" remote. Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com> Link: https://lore.kernel.org/r/20231011185113.140426-5-daan.j.demeyer@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
||
|
Linus Torvalds
|
73be7fb14e |
Including fixes from netfilter and bpf.
Current release - regressions:
- eth: stmmac: fix failure to probe without MAC interface specified
Current release - new code bugs:
- docs: netlink: fix missing classic_netlink doc reference
Previous releases - regressions:
- deal with integer overflows in kmalloc_reserve()
- use sk_forward_alloc_get() in sk_get_meminfo()
- bpf_sk_storage: fix the missing uncharge in sk_omem_alloc
- fib: avoid warn splat in flow dissector after packet mangling
- skb_segment: call zero copy functions before using skbuff frags
- eth: sfc: check for zero length in EF10 RX prefix
Previous releases - always broken:
- af_unix: fix msg_controllen test in scm_pidfd_recv() for
MSG_CMSG_COMPAT
- xsk: fix xsk_build_skb() dereferencing possible ERR_PTR()
- netfilter:
- nft_exthdr: fix non-linear header modification
- xt_u32, xt_sctp: validate user space input
- nftables: exthdr: fix 4-byte stack OOB write
- nfnetlink_osf: avoid OOB read
- one more fix for the garbage collection work from last release
- igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU
- bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t
- handshake: fix null-deref in handshake_nl_done_doit()
- ip: ignore dst hint for multipath routes to ensure packets
are hashed across the nexthops
- phy: micrel:
- correct bit assignments for cable test errata
- disable EEE according to the KSZ9477 errata
Misc:
- docs/bpf: document compile-once-run-everywhere (CO-RE) relocations
- Revert "net: macsec: preserve ingress frame ordering", it appears
to have been developed against an older kernel, problem doesn't
exist upstream
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking updates from Jakub Kicinski:
"Including fixes from netfilter and bpf.
Current release - regressions:
- eth: stmmac: fix failure to probe without MAC interface specified
Current release - new code bugs:
- docs: netlink: fix missing classic_netlink doc reference
Previous releases - regressions:
- deal with integer overflows in kmalloc_reserve()
- use sk_forward_alloc_get() in sk_get_meminfo()
- bpf_sk_storage: fix the missing uncharge in sk_omem_alloc
- fib: avoid warn splat in flow dissector after packet mangling
- skb_segment: call zero copy functions before using skbuff frags
- eth: sfc: check for zero length in EF10 RX prefix
Previous releases - always broken:
- af_unix: fix msg_controllen test in scm_pidfd_recv() for
MSG_CMSG_COMPAT
- xsk: fix xsk_build_skb() dereferencing possible ERR_PTR()
- netfilter:
- nft_exthdr: fix non-linear header modification
- xt_u32, xt_sctp: validate user space input
- nftables: exthdr: fix 4-byte stack OOB write
- nfnetlink_osf: avoid OOB read
- one more fix for the garbage collection work from last release
- igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU
- bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t
- handshake: fix null-deref in handshake_nl_done_doit()
- ip: ignore dst hint for multipath routes to ensure packets are
hashed across the nexthops
- phy: micrel:
- correct bit assignments for cable test errata
- disable EEE according to the KSZ9477 errata
Misc:
- docs/bpf: document compile-once-run-everywhere (CO-RE) relocations
- Revert "net: macsec: preserve ingress frame ordering", it appears
to have been developed against an older kernel, problem doesn't
exist upstream"
* tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (95 commits)
net: enetc: distinguish error from valid pointers in enetc_fixup_clear_rss_rfs()
Revert "net: team: do not use dynamic lockdep key"
net: hns3: remove GSO partial feature bit
net: hns3: fix the port information display when sfp is absent
net: hns3: fix invalid mutex between tc qdisc and dcb ets command issue
net: hns3: fix debugfs concurrency issue between kfree buffer and read
net: hns3: fix byte order conversion issue in hclge_dbg_fd_tcam_read()
net: hns3: Support query tx timeout threshold by debugfs
net: hns3: fix tx timeout issue
net: phy: Provide Module 4 KSZ9477 errata (DS80000754C)
netfilter: nf_tables: Unbreak audit log reset
netfilter: ipset: add the missing IP_SET_HASH_WITH_NET0 macro for ip_set_hash_netportnet.c
netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction
netfilter: nf_tables: uapi: Describe NFTA_RULE_CHAIN_ID
netfilter: nfnetlink_osf: avoid OOB read
netfilter: nftables: exthdr: fix 4-byte stack OOB write
selftests/bpf: Check bpf_sk_storage has uncharged sk_omem_alloc
bpf: bpf_sk_storage: Fix the missing uncharge in sk_omem_alloc
bpf: bpf_sk_storage: Fix invalid wait context lockdep report
s390/bpf: Pass through tail call counter in trampolines
...
|
||
|
Kuniyuki Iwashima
|
ade32bd8a7 |
af_unix: Fix data-race around unix_tot_inflight.
unix_tot_inflight is changed under spin_lock(unix_gc_lock), but unix_release_sock() reads it locklessly. Let's use READ_ONCE() for unix_tot_inflight. Note that the writer side was marked by commit |
||
|
Kuniyuki Iwashima
|
0bc36c0650 |
af_unix: Fix data-races around user->unix_inflight.
user->unix_inflight is changed under spin_lock(unix_gc_lock),
but too_many_unix_fds() reads it locklessly.
Let's annotate the write/read accesses to user->unix_inflight.
BUG: KCSAN: data-race in unix_attach_fds / unix_inflight
write to 0xffffffff8546f2d0 of 8 bytes by task 44798 on cpu 1:
unix_inflight+0x157/0x180 net/unix/scm.c:66
unix_attach_fds+0x147/0x1e0 net/unix/scm.c:123
unix_scm_to_skb net/unix/af_unix.c:1827 [inline]
unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950
unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline]
unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292
sock_sendmsg_nosec net/socket.c:725 [inline]
sock_sendmsg+0x148/0x160 net/socket.c:748
____sys_sendmsg+0x4e4/0x610 net/socket.c:2494
___sys_sendmsg+0xc6/0x140 net/socket.c:2548
__sys_sendmsg+0x94/0x140 net/socket.c:2577
__do_sys_sendmsg net/socket.c:2586 [inline]
__se_sys_sendmsg net/socket.c:2584 [inline]
__x64_sys_sendmsg+0x45/0x50 net/socket.c:2584
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
read to 0xffffffff8546f2d0 of 8 bytes by task 44814 on cpu 0:
too_many_unix_fds net/unix/scm.c:101 [inline]
unix_attach_fds+0x54/0x1e0 net/unix/scm.c:110
unix_scm_to_skb net/unix/af_unix.c:1827 [inline]
unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950
unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline]
unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292
sock_sendmsg_nosec net/socket.c:725 [inline]
sock_sendmsg+0x148/0x160 net/socket.c:748
____sys_sendmsg+0x4e4/0x610 net/socket.c:2494
___sys_sendmsg+0xc6/0x140 net/socket.c:2548
__sys_sendmsg+0x94/0x140 net/socket.c:2577
__do_sys_sendmsg net/socket.c:2586 [inline]
__se_sys_sendmsg net/socket.c:2584 [inline]
__x64_sys_sendmsg+0x45/0x50 net/socket.c:2584
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
value changed: 0x000000000000000c -> 0x000000000000000d
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 44814 Comm: systemd-coredum Not tainted 6.4.0-11989-g6843306689af #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Fixes:
|
||
|
Linus Torvalds
|
adfd671676 |
sysctl-6.6-rc1
Long ago we set out to remove the kitchen sink on kernel/sysctl.c arrays and placings sysctls to their own sybsystem or file to help avoid merge conflicts. Matthew Wilcox pointed out though that if we're going to do that we might as well also *save* space while at it and try to remove the extra last sysctl entry added at the end of each array, a sentintel, instead of bloating the kernel by adding a new sentinel with each array moved. Doing that was not so trivial, and has required slowing down the moves of kernel/sysctl.c arrays and measuring the impact on size by each new move. The complex part of the effort to help reduce the size of each sysctl is being done by the patient work of el señor Don Joel Granados. A lot of this is truly painful code refactoring and testing and then trying to measure the savings of each move and removing the sentinels. Although Joel already has code which does most of this work, experience with sysctl moves in the past shows is we need to be careful due to the slew of odd build failures that are possible due to the amount of random Kconfig options sysctls use. To that end Joel's work is split by first addressing the major housekeeping needed to remove the sentinels, which is part of this merge request. The rest of the work to actually remove the sentinels will be done later in future kernel releases. At first I was only going to send his first 7 patches of his patch series, posted 1 month ago, but in retrospect due to the testing the changes have received in linux-next and the minor changes they make this goes with the entire set of patches Joel had planned: just sysctl house keeping. There are networking changes but these are part of the house keeping too. The preliminary math is showing this will all help reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array where we are able to remove each sentinel in the future. That also means there is no more bloating the kernel with the extra ~64 bytes per array moved as no new sentinels are created. Most of this has been in linux-next for about a month, the last 7 patches took a minor refresh 2 week ago based on feedback. -----BEGIN PGP SIGNATURE----- iQJGBAABCgAwFiEENnNq2KuOejlQLZofziMdCjCSiKcFAmTuVnMSHG1jZ3JvZkBr ZXJuZWwub3JnAAoJEM4jHQowkoinIckP/imvRlfkO6L0IP7MmJBRPtwY01rsTAKO Q14dZ//bG4DVQeGl1FdzrF6hhuLgekU0qW1YDFIWiCXO7CbaxaNBPSUkeW6ReVoC R/VHNUPxSR1PWQy1OTJV2t4XKri2sB7ijmUsfsATtISwhei9bggTHEysShtP4tv+ U87DzhoqMnbYIsfMo49KCqOa1Qm7TmjC1a7WAp6Fph3GJuXAzZR5pXpsd0NtOZ9x Ud5RT22icnQpMl7K+yPsqY6XcS5JkgBe/WbSzMAUkYZvBZFBq9t2D+OW5h9TZMhw piJWQ9X0Rm7qI2D15mJfXwaOhhyDhWci391hzdJmS6DI0prf6Ma2NFdAWOt/zomI uiRujS4bGeBUaK5F4TX2WQ1+jdMtAZ+0FncFnzt4U8q7dzUc91uVCm6iHW3gcfAb N7OEg2ZL0gkkgCZHqKxN8wpNQiC2KwnNk+HLAbnL2a/oJYfBtdopQmlxWfrN2hpF xxROiENqk483BRdMXDq6DR/gyDZmZWCobXIglSzlqCOjCOcLbDziIJ7pJk83ok09 h/QnXTYHf9protBq9OIQesgh2pwNzBBLifK84KZLKcb7IbdIKjpQrW5STp04oNGf wcGJzEz8tXUe0UKyMM47AcHQGzIy6cdXNLjyF8a+m7rnZzr1ndnMqZyRStZzuQin AUg2VWHKPmW9 =sq2p -----END PGP SIGNATURE----- Merge tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull sysctl updates from Luis Chamberlain: "Long ago we set out to remove the kitchen sink on kernel/sysctl.c arrays and placings sysctls to their own sybsystem or file to help avoid merge conflicts. Matthew Wilcox pointed out though that if we're going to do that we might as well also *save* space while at it and try to remove the extra last sysctl entry added at the end of each array, a sentintel, instead of bloating the kernel by adding a new sentinel with each array moved. Doing that was not so trivial, and has required slowing down the moves of kernel/sysctl.c arrays and measuring the impact on size by each new move. The complex part of the effort to help reduce the size of each sysctl is being done by the patient work of el señor Don Joel Granados. A lot of this is truly painful code refactoring and testing and then trying to measure the savings of each move and removing the sentinels. Although Joel already has code which does most of this work, experience with sysctl moves in the past shows is we need to be careful due to the slew of odd build failures that are possible due to the amount of random Kconfig options sysctls use. To that end Joel's work is split by first addressing the major housekeeping needed to remove the sentinels, which is part of this merge request. The rest of the work to actually remove the sentinels will be done later in future kernel releases. The preliminary math is showing this will all help reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array where we are able to remove each sentinel in the future. That also means there is no more bloating the kernel with the extra ~64 bytes per array moved as no new sentinels are created" * tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: sysctl: Use ctl_table_size as stopping criteria for list macro sysctl: SIZE_MAX->ARRAY_SIZE in register_net_sysctl vrf: Update to register_net_sysctl_sz networking: Update to register_net_sysctl_sz netfilter: Update to register_net_sysctl_sz ax.25: Update to register_net_sysctl_sz sysctl: Add size to register_net_sysctl function sysctl: Add size arg to __register_sysctl_init sysctl: Add size to register_sysctl sysctl: Add a size arg to __register_sysctl_table sysctl: Add size argument to init_header sysctl: Add ctl_table_size to ctl_table_header sysctl: Use ctl_table_header in list_for_each_table_entry sysctl: Prefer ctl_table_header in proc_sysctl |
||
|
Joel Granados
|
c899710fe7 |
networking: Update to register_net_sysctl_sz
Move from register_net_sysctl to register_net_sysctl_sz for all the
networking related files. Do this while making sure to mirror the NULL
assignments with a table_size of zero for the unprivileged users.
We need to move to the new function in preparation for when we change
SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do
so would erroneously allow ARRAY_SIZE() to be called on a pointer. We
hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all
the relevant net sysctl registering functions to register_net_sysctl_sz
in subsequent commits.
An additional size function was added to the following files in order to
calculate the size of an array that is defined in another file:
include/net/ipv6.h
net/ipv6/icmp.c
net/ipv6/route.c
net/ipv6/sysctl_net_ipv6.c
Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
|
||
|
Eric Dumazet
|
1ded5e5a59 |
net: annotate data-races around sock->ops
IPV6_ADDRFORM socket option is evil, because it can change sock->ops while other threads might read it. Same issue for sk->sk_family being set to AF_INET. Adding READ_ONCE() over sock->ops reads is needed for sockets that might be impacted by IPV6_ADDRFORM. Note that mptcp_is_tcpsk() can also overwrite sock->ops. Adding annotations for all sk->sk_family reads will require more patches :/ BUG: KCSAN: data-race in ____sys_sendmsg / do_ipv6_setsockopt write to 0xffff888109f24ca0 of 8 bytes by task 4470 on cpu 0: do_ipv6_setsockopt+0x2c5e/0x2ce0 net/ipv6/ipv6_sockglue.c:491 ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012 udpv6_setsockopt+0x95/0xa0 net/ipv6/udp.c:1690 sock_common_setsockopt+0x61/0x70 net/core/sock.c:3663 __sys_setsockopt+0x1c3/0x230 net/socket.c:2273 __do_sys_setsockopt net/socket.c:2284 [inline] __se_sys_setsockopt net/socket.c:2281 [inline] __x64_sys_setsockopt+0x66/0x80 net/socket.c:2281 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff888109f24ca0 of 8 bytes by task 4469 on cpu 1: sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0x349/0x4c0 net/socket.c:2503 ___sys_sendmsg net/socket.c:2557 [inline] __sys_sendmmsg+0x263/0x500 net/socket.c:2643 __do_sys_sendmmsg net/socket.c:2672 [inline] __se_sys_sendmmsg net/socket.c:2669 [inline] __x64_sys_sendmmsg+0x57/0x60 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0xffffffff850e32b8 -> 0xffffffff850da890 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 4469 Comm: syz-executor.1 Not tainted 6.4.0-rc5-syzkaller-00313-g4c605260bc60 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230808135809.2300241-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
|
Eric Dumazet
|
11695c6e96 |
net: add missing data-race annotations around sk->sk_peek_off
sk_getsockopt() runs locklessly, thus we need to annotate the read
of sk->sk_peek_off.
While we are at it, add corresponding annotations to sk_set_peek_off()
and unix_set_peek_off().
Fixes:
|
||
|
Kuniyuki Iwashima
|
ecb4534b6a |
af_unix: Terminate sun_path when bind()ing pathname socket.
kernel test robot reported slab-out-of-bounds access in strlen(). [0] Commit |