The size table is incorrect due to copypaste error,
this reserves more size than needed.
TSTAMP reserved 32 instead of 16 bytes.
TIMEOUT reserved 16 instead of 8 bytes.
Fixes: 5f31edc0676b ("netfilter: conntrack: move extension sizes into core")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Anonymous sets need to be populated once at creation and then they are
bound to rule since 938154b93be8 ("netfilter: nf_tables: reject unbound
anonymous set before commit phase"), otherwise transaction reports
EINVAL.
Userspace does not need to delete elements of anonymous sets that are
not yet bound, reject this with EOPNOTSUPP.
From flush command path, skip anonymous sets, they are expected to be
bound already. Otherwise, EINVAL is hit at the end of this transaction
for unbound sets.
Fixes: 96518518cc41 ("netfilter: add nftables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Skip GC run if iterator rewinds to the beginning with EAGAIN, otherwise GC
might collect the same element more than once.
Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_trans_gc_queue_sync() enqueues the GC transaction and it allocates a
new one. If this allocation fails, then stop this GC sync run and retry
later.
Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
pipapo needs to enqueue GC transactions for catchall elements through
nft_trans_gc_queue_sync(). Add nft_trans_gc_catchall_sync() and
nft_trans_gc_catchall_async() to handle GC transaction queueing
accordingly.
Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
rbtree GC does not modify the datastructure, instead it collects expired
elements and it enqueues a GC transaction. Use a read spinlock instead
to avoid data contention while GC worker is running.
Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Chain binding only requires the rule addition/insertion command within
the same transaction. Removal of rules from chain bindings within the
same transaction makes no sense, userspace does not utilize this
feature. Replace nft_chain_is_bound() check to nft_chain_binding() in
rule deletion commands. Replace command implies a rule deletion, reject
this command too.
Rule flush command can also safely rely on this nft_chain_binding()
check because unbound chains are not allowed since 62e1e94b246e
("netfilter: nf_tables: reject unbound chain set before commit phase").
Fixes: d0e2c7de92c7 ("netfilter: nf_tables: add NFT_CHAIN_BINDING")
Reported-by: Kevin Rich <kevinrich1337@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Merge tag 'nf-23-09-06' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Florian Westphal says:
====================
netfilter updates for net
This PR contains nf_tables updates for your *net* tree.
This time almost all fixes are for old bugs:
First patch fixes a 4-byte stack OOB write, from myself.
This was broken ever since nftables was switches from 128 to 32bit
register addressing in v4.1.
2nd patch fixes an out-of-bounds read.
This has been broken ever since xt_osf got added in 2.6.31, the bug
was then just moved around during refactoring, from Wander Lairson Costa.
3rd patch adds a missing enum description, from Phil Sutter.
4th patch fixes a UaF inftables that occurs when userspace adds
elements with a timeout so small that expiration happens while the
transaction is still in progress. Fix from Pablo Neira Ayuso.
Patch 5 fixes a memory out of bounds access, this was
broken since v4.20. Patch from Kyle Zeng and Jozsef Kadlecsik.
Patch 6 fixes another bogus memory access when building audit
record. Bug added in the previous pull request, fix from Pablo.
netfilter pull request 2023-09-06
* tag 'nf-23-09-06' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
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
====================
Link: https://lore.kernel.org/r/20230906162525.11079-1-fw@strlen.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:
====================
pull-request: bpf 2023-09-06
We've added 9 non-merge commits during the last 6 day(s) which contain
a total of 12 files changed, 189 insertions(+), 44 deletions(-).
The main changes are:
1) Fix bpf_sk_storage to address an invalid wait context lockdep
report and another one to address missing omem uncharge,
from Martin KaFai Lau.
2) Two BPF recursion detection related fixes,
from Sebastian Andrzej Siewior.
3) Fix tailcall limit enforcement in trampolines for s390 JIT,
from Ilya Leoshkevich.
4) Fix a sockmap refcount race where skbs in sk_psock_backlog can
be referenced after user space side has already skb_consumed them,
from John Fastabend.
5) Fix BPF CI flake/race wrt sockmap vsock write test where
the transport endpoint is not connected, from Xu Kuohai.
6) Follow-up doc fix to address a cross-link warning,
from Eduard Zingerman.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
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
bpf: Assign bpf_tramp_run_ctx::saved_run_ctx before recursion check.
bpf: Invoke __bpf_prog_exit_sleepable_recur() on recursion in kern_sys_bpf().
bpf, sockmap: Fix skb refcnt race after locking changes
docs/bpf: Fix "file doesn't exist" warnings in {llvm_reloc,btf}.rst
selftests/bpf: Fix a CI failure caused by vsock write
====================
Link: https://lore.kernel.org/r/20230906095117.16941-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The missing IP_SET_HASH_WITH_NET0 macro in ip_set_hash_netportnet can
lead to the use of wrong `CIDR_POS(c)` for calculating array offsets,
which can lead to integer underflow. As a result, it leads to slab
out-of-bound access.
This patch adds back the IP_SET_HASH_WITH_NET0 macro to
ip_set_hash_netportnet to address the issue.
Fixes: 886503f34d63 ("netfilter: ipset: actually allow allowable CIDR 0 in hash:net,port,net")
Suggested-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Kyle Zeng <zengyhkyle@gmail.com>
Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
New elements in this transaction might expired before such transaction
ends. Skip sync GC for such elements otherwise commit path might walk
over an already released object. Once transaction is finished, async GC
will collect such expired element.
Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
The opt_num field is controlled by user mode and is not currently
validated inside the kernel. An attacker can take advantage of this to
trigger an OOB read and potentially leak information.
BUG: KASAN: slab-out-of-bounds in nf_osf_match_one+0xbed/0xd10 net/netfilter/nfnetlink_osf.c:88
Read of size 2 at addr ffff88804bc64272 by task poc/6431
CPU: 1 PID: 6431 Comm: poc Not tainted 6.0.0-rc4 #1
Call Trace:
nf_osf_match_one+0xbed/0xd10 net/netfilter/nfnetlink_osf.c:88
nf_osf_find+0x186/0x2f0 net/netfilter/nfnetlink_osf.c:281
nft_osf_eval+0x37f/0x590 net/netfilter/nft_osf.c:47
expr_call_ops_eval net/netfilter/nf_tables_core.c:214
nft_do_chain+0x2b0/0x1490 net/netfilter/nf_tables_core.c:264
nft_do_chain_ipv4+0x17c/0x1f0 net/netfilter/nft_chain_filter.c:23
[..]
Also add validation to genre, subtype and version fields.
Fixes: 11eeef41d5f6 ("netfilter: passive OS fingerprint xtables match")
Reported-by: Lucas Leong <wmliang@infosec.exchange>
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
If priv->len is a multiple of 4, then dst[len / 4] can write past
the destination array which leads to stack corruption.
This construct is necessary to clean the remainder of the register
in case ->len is NOT a multiple of the register size, so make it
conditional just like nft_payload.c does.
The bug was added in 4.1 cycle and then copied/inherited when
tcp/sctp and ip option support was added.
Bug reported by Zero Day Initiative project (ZDI-CAN-21950,
ZDI-CAN-21951, ZDI-CAN-21961).
Fixes: 49499c3e6e18 ("netfilter: nf_tables: switch registers to 32 bit addressing")
Fixes: 935b7f643018 ("netfilter: nft_exthdr: add TCP option matching")
Fixes: 133dc203d77d ("netfilter: nft_exthdr: Support SCTP chunks")
Fixes: dbb5281a1f84 ("netfilter: nf_tables: add support for matching IPv4 options")
Signed-off-by: Florian Westphal <fw@strlen.de>
__skb_get_hash_symmetric() was added to compute a symmetric hash over
the protocol, addresses and transport ports, by commit eb70db875671
("packet: Use symmetric hash for PACKET_FANOUT_HASH."). It uses
flow_keys_dissector_symmetric_keys as the flow_dissector to incorporate
IPv4 addresses, IPv6 addresses and ports. However, it should not specify
the flag as FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL, which stops further
dissection when an IPv6 flow label is encountered, making transport
ports not being incorporated in such case.
As a consequence, the symmetric hash is based on 5-tuple for IPv4 but
3-tuple for IPv6 when flow label is present. It caused a few problems,
e.g. when nft symhash and openvswitch l4_sym rely on the symmetric hash
to perform load balancing as different L4 flows between two given IPv6
addresses would always get the same symmetric hash, leading to uneven
traffic distribution.
Removing the use of FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL makes sure the
symmetric hash is based on 5-tuple for both IPv4 and IPv6 consistently.
Fixes: eb70db875671 ("packet: Use symmetric hash for PACKET_FANOUT_HASH.")
Reported-by: Lars Ekman <uablrek@gmail.com>
Closes: https://github.com/antrea-io/antrea/issues/5457
Signed-off-by: Quan Tian <qtian@vmware.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a follow up of commit 915d975b2ffa ("net: deal with integer
overflows in kmalloc_reserve()") based on David Laight feedback.
Back in 2010, I failed to realize malicious users could set dev->mtu
to arbitrary values. This mtu has been since limited to 0x7fffffff but
regardless of how big dev->mtu is, it makes no sense for igmpv3_newpack()
to allocate more than IP_MAX_MTU and risk various skb fields overflows.
Fixes: 57e1ab6eaddc ("igmp: refine skb allocations")
Link: https://lore.kernel.org/netdev/d273628df80f45428e739274ab9ecb72@AcuMS.aculab.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: David Laight <David.Laight@ACULAB.COM>
Cc: Kyle Zeng <zengyhkyle@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
kcm_exit_net() should call mutex_destroy() on knet->mutex. This is especially
needed if CONFIG_DEBUG_MUTEXES is enabled.
Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module")
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Link: https://lore.kernel.org/r/20230902170708.1727999-1-syoshida@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
As with sk->sk_shutdown shown in the previous patch, sk->sk_err can be
read locklessly by unix_dgram_sendmsg().
Let's use READ_ONCE() for sk_err as well.
Note that the writer side is marked by commit cc04410af7de ("af_unix:
annotate lockless accesses to sk->sk_err").
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a race where skb's from the sk_psock_backlog can be referenced
after userspace side has already skb_consumed() the sk_buff and its refcnt
dropped to zer0 causing use after free.
The flow is the following:
while ((skb = skb_peek(&psock->ingress_skb))
sk_psock_handle_Skb(psock, skb, ..., ingress)
if (!ingress) ...
sk_psock_skb_ingress
sk_psock_skb_ingress_enqueue(skb)
msg->skb = skb
sk_psock_queue_msg(psock, msg)
skb_dequeue(&psock->ingress_skb)
The sk_psock_queue_msg() puts the msg on the ingress_msg queue. This is
what the application reads when recvmsg() is called. An application can
read this anytime after the msg is placed on the queue. The recvmsg hook
will also read msg->skb and then after user space reads the msg will call
consume_skb(skb) on it effectively free'ing it.
But, the race is in above where backlog queue still has a reference to
the skb and calls skb_dequeue(). If the skb_dequeue happens after the
user reads and free's the skb we have a use after free.
The !ingress case does not suffer from this problem because it uses
sendmsg_*(sk, msg) which does not pass the sk_buff further down the
stack.
The following splat was observed with 'test_progs -t sockmap_listen':
[ 1022.710250][ T2556] general protection fault, ...
[...]
[ 1022.712830][ T2556] Workqueue: events sk_psock_backlog
[ 1022.713262][ T2556] RIP: 0010:skb_dequeue+0x4c/0x80
[ 1022.713653][ T2556] Code: ...
[...]
[ 1022.720699][ T2556] Call Trace:
[ 1022.720984][ T2556] <TASK>
[ 1022.721254][ T2556] ? die_addr+0x32/0x80^M
[ 1022.721589][ T2556] ? exc_general_protection+0x25a/0x4b0
[ 1022.722026][ T2556] ? asm_exc_general_protection+0x22/0x30
[ 1022.722489][ T2556] ? skb_dequeue+0x4c/0x80
[ 1022.722854][ T2556] sk_psock_backlog+0x27a/0x300
[ 1022.723243][ T2556] process_one_work+0x2a7/0x5b0
[ 1022.723633][ T2556] worker_thread+0x4f/0x3a0
[ 1022.723998][ T2556] ? __pfx_worker_thread+0x10/0x10
[ 1022.724386][ T2556] kthread+0xfd/0x130
[ 1022.724709][ T2556] ? __pfx_kthread+0x10/0x10
[ 1022.725066][ T2556] ret_from_fork+0x2d/0x50
[ 1022.725409][ T2556] ? __pfx_kthread+0x10/0x10
[ 1022.725799][ T2556] ret_from_fork_asm+0x1b/0x30
[ 1022.726201][ T2556] </TASK>
To fix we add an skb_get() before passing the skb to be enqueued in the
engress queue. This bumps the skb->users refcnt so that consume_skb()
and kfree_skb will not immediately free the sk_buff. With this we can
be sure the skb is still around when we do the dequeue. Then we just
need to decrement the refcnt or free the skb in the backlog case which
we do by calling kfree_skb() on the ingress case as well as the sendmsg
case.
Before locking change from fixes tag we had the sock locked so we
couldn't race with user and there was no issue here.
Fixes: 799aa7f98d53e ("skmsg: Avoid lock_sock() in sk_psock_backlog()")
Reported-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Xu Kuohai <xukuohai@huawei.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230901202137.214666-1-john.fastabend@gmail.com
The existing code incorrectly casted a negative value (the result of a
subtraction) to an unsigned value without checking. For example, if
/proc/sys/net/ipv6/conf/*/temp_prefered_lft was set to 1, the preferred
lifetime would jump to 4 billion seconds. On my machine and network the
shortest lifetime that avoided underflow was 3 seconds.
Fixes: 76506a986dc3 ("IPv6: fix DESYNC_FACTOR")
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Blamed commit changed:
ptr = kmalloc(size);
if (ptr)
size = ksize(ptr);
to:
size = kmalloc_size_roundup(size);
ptr = kmalloc(size);
This allowed various crash as reported by syzbot [1]
and Kyle Zeng.
Problem is that if @size is bigger than 0x80000001,
kmalloc_size_roundup(size) returns 2^32.
kmalloc_reserve() uses a 32bit variable (obj_size),
so 2^32 is truncated to 0.
kmalloc(0) returns ZERO_SIZE_PTR which is not handled by
skb allocations.
Following trace can be triggered if a netdev->mtu is set
close to 0x7fffffff
We might in the future limit netdev->mtu to more sensible
limit (like KMALLOC_MAX_SIZE).
This patch is based on a syzbot report, and also a report
and tentative fix from Kyle Zeng.
[1]
BUG: KASAN: user-memory-access in __build_skb_around net/core/skbuff.c:294 [inline]
BUG: KASAN: user-memory-access in __alloc_skb+0x3c4/0x6e8 net/core/skbuff.c:527
Write of size 32 at addr 00000000fffffd10 by task syz-executor.4/22554
CPU: 1 PID: 22554 Comm: syz-executor.4 Not tainted 6.1.39-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
Call trace:
dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:279
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:286
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x120/0x1a0 lib/dump_stack.c:106
print_report+0xe4/0x4b4 mm/kasan/report.c:398
kasan_report+0x150/0x1ac mm/kasan/report.c:495
kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:189
memset+0x40/0x70 mm/kasan/shadow.c:44
__build_skb_around net/core/skbuff.c:294 [inline]
__alloc_skb+0x3c4/0x6e8 net/core/skbuff.c:527
alloc_skb include/linux/skbuff.h:1316 [inline]
igmpv3_newpack+0x104/0x1088 net/ipv4/igmp.c:359
add_grec+0x81c/0x1124 net/ipv4/igmp.c:534
igmpv3_send_cr net/ipv4/igmp.c:667 [inline]
igmp_ifc_timer_expire+0x1b0/0x1008 net/ipv4/igmp.c:810
call_timer_fn+0x1c0/0x9f0 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers+0x54c/0x710 kernel/time/timer.c:1790
run_timer_softirq+0x28/0x4c kernel/time/timer.c:1803
_stext+0x380/0xfbc
____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:79
call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:891
do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:84
invoke_softirq kernel/softirq.c:437 [inline]
__irq_exit_rcu+0x1c0/0x4cc kernel/softirq.c:683
irq_exit_rcu+0x14/0x78 kernel/softirq.c:695
el0_interrupt+0x7c/0x2e0 arch/arm64/kernel/entry-common.c:717
__el0_irq_handler_common+0x18/0x24 arch/arm64/kernel/entry-common.c:724
el0t_64_irq_handler+0x10/0x1c arch/arm64/kernel/entry-common.c:729
el0t_64_irq+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Fixes: 12d6c1d3a2ad ("skbuff: Proactively round up to kmalloc bucket size")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Kyle Zeng <zengyhkyle@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Route hints when the nexthop is part of a multipath group causes packets
in the same receive batch to be sent to the same nexthop irrespective of
the multipath hash of the packet. So, do not extract route hint for
packets whose destination is part of a multipath group.
A new SKB flag IP6SKB_MULTIPATH is introduced for this purpose, set the
flag when route is looked up in fib6_select_path() and use it in
ip6_can_use_hint() to check for the existence of the flag.
Fixes: 197dbf24e360 ("ipv6: introduce and uses route look hints for list input.")
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Route hints when the nexthop is part of a multipath group causes packets
in the same receive batch to be sent to the same nexthop irrespective of
the multipath hash of the packet. So, do not extract route hint for
packets whose destination is part of a multipath group.
A new SKB flag IPSKB_MULTIPATH is introduced for this purpose, set the
flag when route is looked up in ip_mkroute_input() and use it in
ip_extract_route_hint() to check for the existence of the flag.
Fixes: 02b24941619f ("ipv4: use dst hint for ipv4 list receive")
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit bf5c25d60861 ("skbuff: in skb_segment, call zerocopy functions
once per nskb") added the call to zero copy functions in skb_segment().
The change introduced a bug in skb_segment() because skb_orphan_frags()
may possibly change the number of fragments or allocate new fragments
altogether leaving nrfrags and frag to point to the old values. This can
cause a panic with stacktrace like the one below.
[ 193.894380] BUG: kernel NULL pointer dereference, address: 00000000000000bc
[ 193.895273] CPU: 13 PID: 18164 Comm: vh-net-17428 Kdump: loaded Tainted: G O 5.15.123+ #26
[ 193.903919] RIP: 0010:skb_segment+0xb0e/0x12f0
[ 194.021892] Call Trace:
[ 194.027422] <TASK>
[ 194.072861] tcp_gso_segment+0x107/0x540
[ 194.082031] inet_gso_segment+0x15c/0x3d0
[ 194.090783] skb_mac_gso_segment+0x9f/0x110
[ 194.095016] __skb_gso_segment+0xc1/0x190
[ 194.103131] netem_enqueue+0x290/0xb10 [sch_netem]
[ 194.107071] dev_qdisc_enqueue+0x16/0x70
[ 194.110884] __dev_queue_xmit+0x63b/0xb30
[ 194.121670] bond_start_xmit+0x159/0x380 [bonding]
[ 194.128506] dev_hard_start_xmit+0xc3/0x1e0
[ 194.131787] __dev_queue_xmit+0x8a0/0xb30
[ 194.138225] macvlan_start_xmit+0x4f/0x100 [macvlan]
[ 194.141477] dev_hard_start_xmit+0xc3/0x1e0
[ 194.144622] sch_direct_xmit+0xe3/0x280
[ 194.147748] __dev_queue_xmit+0x54a/0xb30
[ 194.154131] tap_get_user+0x2a8/0x9c0 [tap]
[ 194.157358] tap_sendmsg+0x52/0x8e0 [tap]
[ 194.167049] handle_tx_zerocopy+0x14e/0x4c0 [vhost_net]
[ 194.173631] handle_tx+0xcd/0xe0 [vhost_net]
[ 194.176959] vhost_worker+0x76/0xb0 [vhost]
[ 194.183667] kthread+0x118/0x140
[ 194.190358] ret_from_fork+0x1f/0x30
[ 194.193670] </TASK>
In this case calling skb_orphan_frags() updated nr_frags leaving nrfrags
local variable in skb_segment() stale. This resulted in the code hitting
i >= nrfrags prematurely and trying to move to next frag_skb using
list_skb pointer, which was NULL, and caused kernel panic. Move the call
to zero copy functions before using frags and nr_frags.
Fixes: bf5c25d60861 ("skbuff: in skb_segment, call zerocopy functions once per nskb")
Signed-off-by: Mohamed Khalfella <mkhalfella@purestorage.com>
Reported-by: Amit Goyal <agoyal@purestorage.com>
Cc: stable@vger.kernel.org
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk->sk_bind_phc is read locklessly. Add corresponding annotations.
Fixes: d463126e23f1 ("net: sock: extend SO_TIMESTAMPING for PHC binding")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk->sk_tsflags can be read locklessly, add corresponding annotations.
Fixes: b9f40e21ef42 ("net-timestamp: move timestamp flags out of sk_flags")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
msk->rmem_fwd_alloc can be read locklessly.
Add mptcp_rmem_fwd_alloc_add(), similar to sk_forward_alloc_add(),
and appropriate READ_ONCE()/WRITE_ONCE() annotations.
Fixes: 6511882cdd82 ("mptcp: allocate fwd memory separately on the rx and tx path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Every time sk->sk_forward_alloc is read locklessly,
add a READ_ONCE().
Add sk_forward_alloc_add() helper to centralize updates,
to reduce number of WRITE_ONCE().
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet_sk_diag_fill() has been changed to use sk_forward_alloc_get(),
but sk_get_meminfo() was forgotten.
Fixes: 292e6077b040 ("net: introduce sk_forward_alloc_get()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:
====================
pull-request: bpf 2023-08-31
We've added 15 non-merge commits during the last 3 day(s) which contain
a total of 17 files changed, 468 insertions(+), 97 deletions(-).
The main changes are:
1) BPF selftest fixes: one flake and one related to clang18 testing,
from Yonghong Song.
2) Fix a d_path BPF selftest failure after fast-forward from Linus'
tree, from Jiri Olsa.
3) Fix a preempt_rt splat in sockmap when using raw_spin_lock_t,
from John Fastabend.
4) Fix a xsk_diag_fill use-after-free race during socket cleanup,
from Magnus Karlsson.
5) Fix xsk_build_skb to address a buggy dereference of an ERR_PTR(),
from Tirthendu Sarkar.
6) Fix a bpftool build warning when compiled with -Wtype-limits,
from Yafang Shao.
7) Several misc fixes and cleanups in standardization docs,
from David Vernet.
8) Fix BPF selftest install to consider no_alu32/cpuv4/bpf-gcc flavors,
from Björn Töpel.
9) Annotate a data race in bpf_long_memcpy for KCSAN, from Daniel Borkmann.
10) Extend documentation with a description for CO-RE relocations,
from Eduard Zingerman.
11) Fix several invalid escape sequence warnings in bpf_doc.py script,
from Vishal Chourasia.
12) Fix the instruction set doc wrt offset of BPF-to-BPF call,
from Will Hawkins.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: Include build flavors for install target
bpf: Annotate bpf_long_memcpy with data_race
selftests/bpf: Fix d_path test
bpf, docs: Fix invalid escape sequence warnings in bpf_doc.py
xsk: Fix xsk_diag use-after-free error during socket cleanup
bpf, docs: s/eBPF/BPF in standards documents
bpf, docs: Add abi.rst document to standardization subdirectory
bpf, docs: Move linux-notes.rst to root bpf docs tree
bpf, sockmap: Fix preempt_rt splat when using raw_spin_lock_t
docs/bpf: Add description for CO-RE relocations
bpf, docs: Correct source of offset for program-local call
selftests/bpf: Fix flaky cgroup_iter_sleepable subtest
xsk: Fix xsk_build_skb() error: 'skb' dereferencing possible ERR_PTR()
bpftool: Fix build warnings with -Wtype-limits
bpf: Prevent inlining of bpf_fentry_test7()
====================
Link: https://lore.kernel.org/r/20230831210019.14417-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fix a use-after-free error that is possible if the xsk_diag interface
is used after the socket has been unbound from the device. This can
happen either due to the socket being closed or the device
disappearing. In the early days of AF_XDP, the way we tested that a
socket was not bound to a device was to simply check if the netdevice
pointer in the xsk socket structure was NULL. Later, a better system
was introduced by having an explicit state variable in the xsk socket
struct. For example, the state of a socket that is on the way to being
closed and has been unbound from the device is XSK_UNBOUND.
The commit in the Fixes tag below deleted the old way of signalling
that a socket is unbound, setting dev to NULL. This in the belief that
all code using the old way had been exterminated. That was
unfortunately not true as the xsk diagnostics code was still using the
old way and thus does not work as intended when a socket is going
down. Fix this by introducing a test against the state variable. If
the socket is in the state XSK_UNBOUND, simply abort the diagnostic's
netlink operation.
Fixes: 18b1ab7aa76b ("xsk: Fix race at socket teardown")
Reported-by: syzbot+822d1359297e2694f873@syzkaller.appspotmail.com
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: syzbot+822d1359297e2694f873@syzkaller.appspotmail.com
Tested-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20230831100119.17408-1-magnus.karlsson@gmail.com
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Merge tag 'nf-23-08-31' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net:
1) Fix mangling of TCP options with non-linear skbuff, from Xiao Liang.
2) OOB read in xt_sctp due to missing sanitization of array length field.
From Wander Lairson Costa.
3) OOB read in xt_u32 due to missing sanitization of array length field.
Also from Wander Lairson Costa.
All of them above, always broken for several releases.
4) Missing audit log for set element reset command, from Phil Sutter.
5) Missing audit log for rule reset command, also from Phil.
These audit log support are missing in 6.5.
* tag 'nf-23-08-31' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: nf_tables: Audit log rule reset
netfilter: nf_tables: Audit log setelem reset
netfilter: xt_u32: validate user space input
netfilter: xt_sctp: validate the flag_info count
netfilter: nft_exthdr: Fix non-linear header modification
====================
Link: https://lore.kernel.org/r/20230830235935.465690-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Resetting rules' stateful data happens outside of the transaction logic,
so 'get' and 'dump' handlers have to emit audit log entries themselves.
Fixes: 8daa8fde3fc3f ("netfilter: nf_tables: Introduce NFT_MSG_GETRULE_RESET")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since set element reset is not integrated into nf_tables' transaction
logic, an explicit log call is needed, similar to NFT_MSG_GETOBJ_RESET
handling.
For the sake of simplicity, catchall element reset will always generate
a dedicated log entry. This relieves nf_tables_dump_set() from having to
adjust the logged element count depending on whether a catchall element
was found or not.
Fixes: 079cd633219d7 ("netfilter: nf_tables: Introduce NFT_MSG_GETSETELEM_RESET")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The xt_u32 module doesn't validate the fields in the xt_u32 structure.
An attacker may take advantage of this to trigger an OOB read by setting
the size fields with a value beyond the arrays boundaries.
Add a checkentry function to validate the structure.
This was originally reported by the ZDI project (ZDI-CAN-18408).
Fixes: 1b50b8a371e9 ("[NETFILTER]: Add u32 match")
Cc: stable@vger.kernel.org
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
sctp_mt_check doesn't validate the flag_count field. An attacker can
take advantage of that to trigger a OOB read and leak memory
information.
Add the field validation in the checkentry function.
Fixes: 2e4e6a17af35 ("[NETFILTER] x_tables: Abstraction layer for {ip,ip6,arp}_tables")
Cc: stable@vger.kernel.org
Reported-by: Lucas Leong <wmliang@infosec.exchange>
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix skb_ensure_writable() size. Don't use nft_tcp_header_pointer() to
make it explicit that pointers point to the packet (not local buffer).
Fixes: 99d1712bc41c ("netfilter: exthdr: tcp option set support")
Fixes: 7890cbea66e7 ("netfilter: exthdr: add support for tcp option removal")
Cc: stable@vger.kernel.org
Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
commit edf391ff1723 ("snmp: add missing counters for RFC 4293") had
already added OutOctets for RFC 4293. In commit 2d8dbb04c63e ("snmp: fix
OutOctets counter to include forwarded datagrams"), OutOctets was
counted again, but not removed from ip_output().
According to RFC 4293 "3.2.3. IP Statistics Tables",
ipipIfStatsOutTransmits is not equal to ipIfStatsOutForwDatagrams. So
"IPSTATS_MIB_OUTOCTETS must be incremented when incrementing" is not
accurate. And IPSTATS_MIB_OUTOCTETS should be counted after fragment.
This patch reverts commit 2d8dbb04c63e ("snmp: fix OutOctets counter to
include forwarded datagrams") and move IPSTATS_MIB_OUTOCTETS to
ip_finish_output2 for ipv4.
Reviewed-by: Filip Pudak <filip.pudak@windriver.com>
Signed-off-by: Heng Guo <heng.guo@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sockmap and sockhash maps are a collection of psocks that are
objects representing a socket plus a set of metadata needed
to manage the BPF programs associated with the socket. These
maps use the stab->lock to protect from concurrent operations
on the maps, e.g. trying to insert to objects into the array
at the same time in the same slot. Additionally, a sockhash map
has a bucket lock to protect iteration and insert/delete into
the hash entry.
Each psock has a psock->link which is a linked list of all the
maps that a psock is attached to. This allows a psock (socket)
to be included in multiple sockmap and sockhash maps. This
linked list is protected the psock->link_lock.
They _must_ be nested correctly to avoid deadlock:
lock(stab->lock)
: do BPF map operations and psock insert/delete
lock(psock->link_lock)
: add map to psock linked list of maps
unlock(psock->link_lock)
unlock(stab->lock)
For non PREEMPT_RT kernels both raw_spin_lock_t and spin_lock_t
are guaranteed to not sleep. But, with PREEMPT_RT kernels the
spin_lock_t variants may sleep. In the current code we have
many patterns like this:
rcu_critical_section:
raw_spin_lock(stab->lock)
spin_lock(psock->link_lock) <- may sleep ouch
spin_unlock(psock->link_lock)
raw_spin_unlock(stab->lock)
rcu_critical_section
Nesting spin_lock() inside a raw_spin_lock() violates locking
rules for PREEMPT_RT kernels. And additionally we do alloc(GFP_ATOMICS)
inside the stab->lock, but those might sleep on PREEMPT_RT kernels.
The result is splats like this:
./test_progs -t sockmap_basic
[ 33.344330] bpf_testmod: loading out-of-tree module taints kernel.
[ 33.441933]
[ 33.442089] =============================
[ 33.442421] [ BUG: Invalid wait context ]
[ 33.442763] 6.5.0-rc5-01731-gec0ded2e0282 #4958 Tainted: G O
[ 33.443320] -----------------------------
[ 33.443624] test_progs/2073 is trying to lock:
[ 33.443960] ffff888102a1c290 (&psock->link_lock){....}-{3:3}, at: sock_map_update_common+0x2c2/0x3d0
[ 33.444636] other info that might help us debug this:
[ 33.444991] context-{5:5}
[ 33.445183] 3 locks held by test_progs/2073:
[ 33.445498] #0: ffff88811a208d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: sock_map_update_elem_sys+0xff/0x330
[ 33.446159] #1: ffffffff842539e0 (rcu_read_lock){....}-{1:3}, at: sock_map_update_elem_sys+0xf5/0x330
[ 33.446809] #2: ffff88810d687240 (&stab->lock){+...}-{2:2}, at: sock_map_update_common+0x177/0x3d0
[ 33.447445] stack backtrace:
[ 33.447655] CPU: 10 PID
To fix observe we can't readily remove the allocations (for that
we would need to use/create something similar to bpf_map_alloc). So
convert raw_spin_lock_t to spin_lock_t. We note that sock_map_update
that would trigger the allocate and potential sleep is only allowed
through sys_bpf ops and via sock_ops which precludes hw interrupts
and low level atomic sections in RT preempt kernel. On non RT
preempt kernel there are no changes here and spin locks sections
and alloc(GFP_ATOMIC) are still not sleepable.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230830053517.166611-1-john.fastabend@gmail.com
Currently, xsk_build_skb() is a function that builds skb in two possible
ways and then is ended with common error handling.
We can distinguish four possible error paths and handling in xsk_build_skb():
1. sock_alloc_send_skb fails: Retry (skb is NULL).
2. skb_store_bits fails : Free skb and retry.
3. MAX_SKB_FRAGS exceeded: Free skb, cleanup and drop packet.
4. alloc_page fails for frag: Retry page allocation w/o freeing skb
1] and 3] can happen in xsk_build_skb_zerocopy(), which is one of the
two code paths responsible for building skb. Common error path in
xsk_build_skb() assumes that in case errno != -EAGAIN, skb is a valid
pointer, which is wrong as kernel test robot reports that in
xsk_build_skb_zerocopy() other errno values are returned for skb being
NULL.
To fix this, set -EOVERFLOW as error when MAX_SKB_FRAGS are exceeded
and packet needs to be dropped in both xsk_build_skb() and
xsk_build_skb_zerocopy() and use this to distinguish against all other
error cases. Also, add explicit kfree_skb() for 3] so that handling
of 1], 2], and 3] becomes identical where allocation needs to be retried.
Fixes: cf24f5a5feea ("xsk: add support for AF_XDP multi-buffer on Tx path")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Tirthendu Sarkar <tirthendu.sarkar@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Closes: https://lore.kernel.org/r/202307210434.OjgqFcbB-lkp@intel.com
Link: https://lore.kernel.org/bpf/20230823144713.2231808-1-tirthendu.sarkar@intel.com
With latest clang18, I hit test_progs failures for the following test:
#13/2 bpf_cookie/multi_kprobe_link_api:FAIL
#13/3 bpf_cookie/multi_kprobe_attach_api:FAIL
#13 bpf_cookie:FAIL
#75 fentry_fexit:FAIL
#76/1 fentry_test/fentry:FAIL
#76 fentry_test:FAIL
#80/1 fexit_test/fexit:FAIL
#80 fexit_test:FAIL
#110/1 kprobe_multi_test/skel_api:FAIL
#110/2 kprobe_multi_test/link_api_addrs:FAIL
#110/3 kprobe_multi_test/link_api_syms:FAIL
#110/4 kprobe_multi_test/attach_api_pattern:FAIL
#110/5 kprobe_multi_test/attach_api_addrs:FAIL
#110/6 kprobe_multi_test/attach_api_syms:FAIL
#110 kprobe_multi_test:FAIL
For example, for #13/2, the error messages are:
[...]
kprobe_multi_test_run:FAIL:kprobe_test7_result unexpected kprobe_test7_result: actual 0 != expected 1
[...]
kprobe_multi_test_run:FAIL:kretprobe_test7_result unexpected kretprobe_test7_result: actual 0 != expected 1
clang17 does not have this issue.
Further investigation shows that kernel func bpf_fentry_test7(), used in
the above tests, is inlined by the compiler although it is marked as
noinline.
int noinline bpf_fentry_test7(struct bpf_fentry_test_t *arg)
{
return (long)arg;
}
It is known that for simple functions like the above (e.g. just returning
a constant or an input argument), the clang compiler may still do inlining
for a noinline function. Adding 'asm volatile ("")' in the beginning of the
bpf_fentry_test7() can prevent inlining.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20230826200843.2210074-1-yonghong.song@linux.dev
