38374 Commits

Author SHA1 Message Date
Jakub Kicinski
6646dc241d Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-03-04

We've added 32 non-merge commits during the last 14 day(s) which contain
a total of 59 files changed, 1038 insertions(+), 473 deletions(-).

The main changes are:

1) Optimize BPF stackmap's build_id retrieval by caching last valid build_id,
   as consecutive stack frames are likely to be in the same VMA and therefore
   have the same build id, from Hao Luo.

2) Several improvements to arm64 BPF JIT, that is, support for JITing
   the atomic[64]_fetch_add, atomic[64]_[fetch_]{and,or,xor} and lastly
   atomic[64]_{xchg|cmpxchg}. Also fix the BTF line info dump for JITed
   programs, from Hou Tao.

3) Optimize generic BPF map batch deletion by only enforcing synchronize_rcu()
   barrier once upon return to user space, from Eric Dumazet.

4) For kernel build parse DWARF and generate BTF through pahole with enabled
   multithreading, from Kui-Feng Lee.

5) BPF verifier usability improvements by making log info more concise and
   replacing inv with scalar type name, from Mykola Lysenko.

6) Two follow-up fixes for BPF prog JIT pack allocator, from Song Liu.

7) Add a new Kconfig to allow for loading kernel modules with non-matching
   BTF type info; their BTF info is then removed on load, from Connor O'Brien.

8) Remove reallocarray() usage from bpftool and switch to libbpf_reallocarray()
   in order to fix compilation errors for older glibc, from Mauricio Vásquez.

9) Fix libbpf to error on conflicting name in BTF when type declaration
   appears before the definition, from Xu Kuohai.

10) Fix issue in BPF preload for in-kernel light skeleton where loaded BPF
    program fds prevent init process from setting up fd 0-2, from Yucong Sun.

11) Fix libbpf reuse of pinned perf RB map when max_entries is auto-determined
    by libbpf, from Stijn Tintel.

12) Several cleanups for libbpf and a fix to enforce perf RB map #pages to be
    non-zero, from Yuntao Wang.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (32 commits)
  bpf: Small BPF verifier log improvements
  libbpf: Add a check to ensure that page_cnt is non-zero
  bpf, x86: Set header->size properly before freeing it
  x86: Disable HAVE_ARCH_HUGE_VMALLOC on 32-bit x86
  bpf, test_run: Fix overflow in XDP frags bpf_test_finish
  selftests/bpf: Update btf_dump case for conflicting names
  libbpf: Skip forward declaration when counting duplicated type names
  bpf: Add some description about BPF_JIT_ALWAYS_ON in Kconfig
  bpf, docs: Add a missing colon in verifier.rst
  bpf: Cache the last valid build_id
  libbpf: Fix BPF_MAP_TYPE_PERF_EVENT_ARRAY auto-pinning
  bpf, selftests: Use raw_tp program for atomic test
  bpf, arm64: Support more atomic operations
  bpftool: Remove redundant slashes
  bpf: Add config to allow loading modules with BTF mismatches
  bpf, arm64: Feed byte-offset into bpf line info
  bpf, arm64: Call build_prologue() first in first JIT pass
  bpf: Fix issue with bpf preload module taking over stdout/stdin of kernel.
  bpftool: Bpf skeletons assert type sizes
  bpf: Cleanup comments
  ...
====================

Link: https://lore.kernel.org/r/20220304164313.31675-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-04 19:28:17 -08:00
Jakub Kicinski
80901bff81 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
net/batman-adv/hard-interface.c
  commit 690bb6fb64f5 ("batman-adv: Request iflink once in batadv-on-batadv check")
  commit 6ee3c393eeb7 ("batman-adv: Demote batadv-on-batadv skip error message")
https://lore.kernel.org/all/20220302163049.101957-1-sw@simonwunderlich.de/

net/smc/af_smc.c
  commit 4d08b7b57ece ("net/smc: Fix cleanup when register ULP fails")
  commit 462791bbfa35 ("net/smc: add sysctl interface for SMC")
https://lore.kernel.org/all/20220302112209.355def40@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-03 11:55:12 -08:00
Mykola Lysenko
7df5072cc0 bpf: Small BPF verifier log improvements
In particular these include:

  1) Remove output of inv for scalars in print_verifier_state
  2) Replace inv with scalar in verifier error messages
  3) Remove _value suffixes for umin/umax/s32_min/etc (except map_value)
  4) Remove output of id=0
  5) Remove output of ref_obj_id=0

Signed-off-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220301222745.1667206-1-mykolal@fb.com
2022-03-03 16:54:10 +01:00
Linus Torvalds
5859a2b199 Merge branch 'ucount-rlimit-fixes-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull ucounts fix from Eric Biederman:
 "Etienne Dechamps recently found a regression caused by enforcing
  RLIMIT_NPROC for root where the rlimit was not previously enforced.

  Michal Koutný had previously pointed out the inconsistency in
  enforcing the RLIMIT_NPROC that had been on the root owned process
  after the root user creates a user namespace.

  Which makes the fix for the regression simply removing the
  inconsistency"

* 'ucount-rlimit-fixes-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ucounts: Fix systemd LimitNPROC with private users regression
2022-03-02 16:20:04 -08:00
Song Liu
676b2daaba bpf, x86: Set header->size properly before freeing it
On do_jit failure path, the header is freed by bpf_jit_binary_pack_free.
While bpf_jit_binary_pack_free doesn't require proper ro_header->size,
bpf_prog_pack_free still uses it. Set header->size in bpf_int_jit_compile
before calling bpf_jit_binary_pack_free.

Fixes: 1022a5498f6f ("bpf, x86_64: Use bpf_jit_binary_pack_alloc")
Fixes: 33c9805860e5 ("bpf: Introduce bpf_jit_binary_pack_[alloc|finalize|free]")
Reported-by: Kui-Feng Lee <kuifeng@fb.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220302175126.247459-3-song@kernel.org
2022-03-02 13:24:37 -08:00
Tiezhu Yang
b664e255ba bpf: Add some description about BPF_JIT_ALWAYS_ON in Kconfig
When CONFIG_BPF_JIT_ALWAYS_ON is enabled, /proc/sys/net/core/bpf_jit_enable
is permanently set to 1 and setting any other value than that will return
failure.

Add the above description in the help text of config BPF_JIT_ALWAYS_ON, and
then we can distinguish between BPF_JIT_ALWAYS_ON and BPF_JIT_DEFAULT_ON.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/1645523826-18149-2-git-send-email-yangtiezhu@loongson.cn
2022-03-01 00:28:06 +01:00
Hao Luo
ceac059ed4 bpf: Cache the last valid build_id
For binaries that are statically linked, consecutive stack frames are
likely to be in the same VMA and therefore have the same build id.

On a real-world workload, we observed that 66% of CPU cycles in
__bpf_get_stackid() were spent on build_id_parse() and find_vma().

As an optimization for this case, we can cache the previous frame's
VMA, if the new frame has the same VMA as the previous one, reuse the
previous one's build id.

We are holding the MM locks as reader across the entire loop, so we
don't need to worry about VMA going away.

Tested through "stacktrace_build_id" and "stacktrace_build_id_nmi" in
test_progs.

Suggested-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/bpf/20220224000531.1265030-1-haoluo@google.com
2022-02-28 18:10:28 +01:00
Connor O'Brien
5e214f2e43 bpf: Add config to allow loading modules with BTF mismatches
BTF mismatch can occur for a separately-built module even when the ABI is
otherwise compatible and nothing else would prevent successfully loading.

Add a new Kconfig to control how mismatches are handled. By default, preserve
the current behavior of refusing to load the module. If MODULE_ALLOW_BTF_MISMATCH
is enabled, load the module but ignore its BTF information.

Suggested-by: Yonghong Song <yhs@fb.com>
Suggested-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Connor O'Brien <connoro@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/CAADnVQJ+OVPnBz8z3vNu8gKXX42jCUqfuvhWAyCQDu8N_yqqwQ@mail.gmail.com
Link: https://lore.kernel.org/bpf/20220223012814.1898677-1-connoro@google.com
2022-02-28 14:17:10 +01:00
Linus Torvalds
98f3e84f8d dma-mapping fix for Linux 5.17
- fix a swiotlb info leak (Halil Pasic)
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Merge tag 'dma-mapping-5.17-1' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fix from Christoph Hellwig:

 - fix a swiotlb info leak (Halil Pasic)

* tag 'dma-mapping-5.17-1' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: fix info leak with DMA_FROM_DEVICE
2022-02-27 12:42:37 -08:00
Linus Torvalds
2293be58d6 Tracing fixes for 5.17:
- rtla (Real-Time Linux Analysis tool): fix typo in man page
 
  - rtla: Update API -e to -E before it is released
 
  - rlla: Error message fix and memory leak fix
 
  - Partially uninline trace event soft disable to shrink text
 
  - Fix function graph start up test
 
  - Have triggers affect the trace instance they are in and not top level
 
  - Have osnoise sleep in the units it says it uses
 
  - Remove unused ftrace stub function
 
  - Remove event probe redundant info from event in the buffer
 
  - Fix group ownership setting in tracefs
 
  - Ensure trace buffer is minimum size to prevent crashes
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Merge tag 'trace-v5.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:

 - rtla (Real-Time Linux Analysis tool):
    - fix typo in man page
    - Update API -e to -E before it is released
    - Error message fix and memory leak fix

 - Partially uninline trace event soft disable to shrink text

 - Fix function graph start up test

 - Have triggers affect the trace instance they are in and not top level

 - Have osnoise sleep in the units it says it uses

 - Remove unused ftrace stub function

 - Remove event probe redundant info from event in the buffer

 - Fix group ownership setting in tracefs

 - Ensure trace buffer is minimum size to prevent crashes

* tag 'trace-v5.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  rtla/osnoise: Fix error message when failing to enable trace instance
  rtla/osnoise: Free params at the exit
  rtla/hist: Make -E the short version of --entries
  tracing: Fix selftest config check for function graph start up test
  tracefs: Set the group ownership in apply_options() not parse_options()
  tracing/osnoise: Make osnoise_main to sleep for microseconds
  ftrace: Remove unused ftrace_startup_enable() stub
  tracing: Ensure trace buffer is at least 4096 bytes large
  tracing: Uninline trace_trigger_soft_disabled() partly
  eprobes: Remove redundant event type information
  tracing: Have traceon and traceoff trigger honor the instance
  tracing: Dump stacktrace trigger to the corresponding instance
  rtla: Fix systme -> system typo on man page
2022-02-26 12:10:17 -08:00
Christophe Leroy
c5229a0bd4 tracing: Fix selftest config check for function graph start up test
CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS is required to test
direct tramp.

Link: https://lkml.kernel.org/r/bdc7e594e13b0891c1d61bc8d56c94b1890eaed7.1640017960.git.christophe.leroy@csgroup.eu

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 21:05:29 -05:00
Yucong Sun
80bebebdac bpf: Fix issue with bpf preload module taking over stdout/stdin of kernel.
In cb80ddc67152 ("bpf: Convert bpf_preload.ko to use light skeleton.")
BPF preload was switched from user mode process to use in-kernel light
skeleton instead. However, in the kernel context, early in the boot
sequence, the first available FD can start from 0, instead of normally
3 for user mode process. So FDs 0 and 1 are then used for loaded BPF
programs and prevent init process from setting up stdin/stdout/stderr on
FD 0, 1, and 2 as expected.

Before the fix:

ls -lah /proc/1/fd/*

lrwx------1 root root 64 Feb 23 17:20 /proc/1/fd/0 -> /dev/null
lrwx------ 1 root root 64 Feb 23 17:20 /proc/1/fd/1 -> /dev/null
lrwx------ 1 root root 64 Feb 23 17:20 /proc/1/fd/2 -> /dev/console
lrwx------ 1 root root 64 Feb 23 17:20 /proc/1/fd/6 -> /dev/console
lrwx------ 1 root root 64 Feb 23 17:20 /proc/1/fd/7 -> /dev/console

After the fix:

ls -lah /proc/1/fd/*

lrwx------ 1 root root 64 Feb 24 21:23 /proc/1/fd/0 -> /dev/console
lrwx------ 1 root root 64 Feb 24 21:23 /proc/1/fd/1 -> /dev/console
lrwx------ 1 root root 64 Feb 24 21:23 /proc/1/fd/2 -> /dev/console

Fix by closing prog FDs after initialization. struct bpf_prog's
themselves are kept alive through direct kernel references taken with
bpf_link_get_from_fd().

Fixes: cb80ddc67152 ("bpf: Convert bpf_preload.ko to use light skeleton.")
Signed-off-by: Yucong Sun <fallentree@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220225185923.2535519-1-fallentree@fb.com
2022-02-25 12:48:35 -08:00
Daniel Bristot de Oliveira
dd990352f0 tracing/osnoise: Make osnoise_main to sleep for microseconds
osnoise's runtime and period are in the microseconds scale, but it is
currently sleeping in the millisecond's scale. This behavior roots in the
usage of hwlat as the skeleton for osnoise.

Make osnoise to sleep in the microseconds scale. Also, move the sleep to
a specialized function.

Link: https://lkml.kernel.org/r/302aa6c7bdf2d131719b22901905e9da122a11b2.1645197336.git.bristot@kernel.org

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 12:07:01 -05:00
Nathan Chancellor
ab2f993c01 ftrace: Remove unused ftrace_startup_enable() stub
When building with clang + CONFIG_DYNAMIC_FTRACE=n + W=1, there is a
warning:

  kernel/trace/ftrace.c:7194:20: error: unused function 'ftrace_startup_enable' [-Werror,-Wunused-function]
  static inline void ftrace_startup_enable(int command) { }
                     ^
  1 error generated.

Clang warns on instances of static inline functions in .c files with W=1
after commit 6863f5643dd7 ("kbuild: allow Clang to find unused static
inline functions for W=1 build").

The ftrace_startup_enable() stub has been unused since
commit e1effa0144a1 ("ftrace: Annotate the ops operation on update"),
where its use outside of the CONFIG_DYNAMIC_TRACE section was replaced
by ftrace_startup_all().  Remove it to resolve the warning.

Link: https://lkml.kernel.org/r/20220214192847.488166-1-nathan@kernel.org

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 12:07:01 -05:00
Sven Schnelle
7acf3a127b tracing: Ensure trace buffer is at least 4096 bytes large
Booting the kernel with 'trace_buf_size=1' give a warning at
boot during the ftrace selftests:

[    0.892809] Running postponed tracer tests:
[    0.892893] Testing tracer function:
[    0.901899] Callback from call_rcu_tasks_trace() invoked.
[    0.983829] Callback from call_rcu_tasks_rude() invoked.
[    1.072003] .. bad ring buffer .. corrupted trace buffer ..
[    1.091944] Callback from call_rcu_tasks() invoked.
[    1.097695] PASSED
[    1.097701] Testing dynamic ftrace: .. filter failed count=0 ..FAILED!
[    1.353474] ------------[ cut here ]------------
[    1.353478] WARNING: CPU: 0 PID: 1 at kernel/trace/trace.c:1951 run_tracer_selftest+0x13c/0x1b0

Therefore enforce a minimum of 4096 bytes to make the selftest pass.

Link: https://lkml.kernel.org/r/20220214134456.1751749-1-svens@linux.ibm.com

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 12:07:01 -05:00
Christophe Leroy
bc82c38a69 tracing: Uninline trace_trigger_soft_disabled() partly
On a powerpc32 build with CONFIG_CC_OPTIMISE_FOR_SIZE, the inline
keyword is not honored and trace_trigger_soft_disabled() appears
approx 50 times in vmlinux.

Adding -Winline to the build, the following message appears:

	./include/linux/trace_events.h:712:1: error: inlining failed in call to 'trace_trigger_soft_disabled': call is unlikely and code size would grow [-Werror=inline]

That function is rather big for an inlined function:

	c003df60 <trace_trigger_soft_disabled>:
	c003df60:	94 21 ff f0 	stwu    r1,-16(r1)
	c003df64:	7c 08 02 a6 	mflr    r0
	c003df68:	90 01 00 14 	stw     r0,20(r1)
	c003df6c:	bf c1 00 08 	stmw    r30,8(r1)
	c003df70:	83 e3 00 24 	lwz     r31,36(r3)
	c003df74:	73 e9 01 00 	andi.   r9,r31,256
	c003df78:	41 82 00 10 	beq     c003df88 <trace_trigger_soft_disabled+0x28>
	c003df7c:	38 60 00 00 	li      r3,0
	c003df80:	39 61 00 10 	addi    r11,r1,16
	c003df84:	4b fd 60 ac 	b       c0014030 <_rest32gpr_30_x>
	c003df88:	73 e9 00 80 	andi.   r9,r31,128
	c003df8c:	7c 7e 1b 78 	mr      r30,r3
	c003df90:	41 a2 00 14 	beq     c003dfa4 <trace_trigger_soft_disabled+0x44>
	c003df94:	38 c0 00 00 	li      r6,0
	c003df98:	38 a0 00 00 	li      r5,0
	c003df9c:	38 80 00 00 	li      r4,0
	c003dfa0:	48 05 c5 f1 	bl      c009a590 <event_triggers_call>
	c003dfa4:	73 e9 00 40 	andi.   r9,r31,64
	c003dfa8:	40 82 00 28 	bne     c003dfd0 <trace_trigger_soft_disabled+0x70>
	c003dfac:	73 ff 02 00 	andi.   r31,r31,512
	c003dfb0:	41 82 ff cc 	beq     c003df7c <trace_trigger_soft_disabled+0x1c>
	c003dfb4:	80 01 00 14 	lwz     r0,20(r1)
	c003dfb8:	83 e1 00 0c 	lwz     r31,12(r1)
	c003dfbc:	7f c3 f3 78 	mr      r3,r30
	c003dfc0:	83 c1 00 08 	lwz     r30,8(r1)
	c003dfc4:	7c 08 03 a6 	mtlr    r0
	c003dfc8:	38 21 00 10 	addi    r1,r1,16
	c003dfcc:	48 05 6f 6c 	b       c0094f38 <trace_event_ignore_this_pid>
	c003dfd0:	38 60 00 01 	li      r3,1
	c003dfd4:	4b ff ff ac 	b       c003df80 <trace_trigger_soft_disabled+0x20>

However it is located in a hot path so inlining it is important.
But forcing inlining of the entire function by using __always_inline
leads to increasing the text size by approx 20 kbytes.

Instead, split the fonction in two parts, one part with the likely
fast path, flagged __always_inline, and a second part out of line.

With this change, on a powerpc32 with CONFIG_CC_OPTIMISE_FOR_SIZE
vmlinux text increases by only 1,4 kbytes, which is partly
compensated by a decrease of vmlinux data by 7 kbytes.

On ppc64_defconfig which has CONFIG_CC_OPTIMISE_FOR_SPEED, this
change reduces vmlinux text by more than 30 kbytes.

Link: https://lkml.kernel.org/r/69ce0986a52d026d381d612801d978aa4f977460.1644563295.git.christophe.leroy@csgroup.eu

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 12:07:01 -05:00
Steven Rostedt (Google)
b61edd5774 eprobes: Remove redundant event type information
Currently, the event probes save the type of the event they are attached
to when recording the event. For example:

  # echo 'e:switch sched/sched_switch prev_state=$prev_state prev_prio=$prev_prio next_pid=$next_pid next_prio=$next_prio' > dynamic_events
  # cat events/eprobes/switch/format

 name: switch
 ID: 1717
 format:
        field:unsigned short common_type;       offset:0;       size:2; signed:0;
        field:unsigned char common_flags;       offset:2;       size:1; signed:0;
        field:unsigned char common_preempt_count;       offset:3;       size:1; signed:0;
        field:int common_pid;   offset:4;       size:4; signed:1;

        field:unsigned int __probe_type;        offset:8;       size:4; signed:0;
        field:u64 prev_state;   offset:12;      size:8; signed:0;
        field:u64 prev_prio;    offset:20;      size:8; signed:0;
        field:u64 next_pid;     offset:28;      size:8; signed:0;
        field:u64 next_prio;    offset:36;      size:8; signed:0;

 print fmt: "(%u) prev_state=0x%Lx prev_prio=0x%Lx next_pid=0x%Lx next_prio=0x%Lx", REC->__probe_type, REC->prev_state, REC->prev_prio, REC->next_pid, REC->next_prio

The __probe_type adds 4 bytes to every event.

One of the reasons for creating eprobes is to limit what is traced in an
event to be able to limit what is written into the ring buffer. Having
this redundant 4 bytes to every event takes away from this.

The event that is recorded can be retrieved from the event probe itself,
that is available when the trace is happening. For user space tools, it
could simply read the dynamic_event file to find the event they are for.
So there is really no reason to write this information into the ring
buffer for every event.

Link: https://lkml.kernel.org/r/20220218190057.2f5a19a8@gandalf.local.home

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 12:07:01 -05:00
Steven Rostedt (Google)
302e9edd54 tracing: Have traceon and traceoff trigger honor the instance
If a trigger is set on an event to disable or enable tracing within an
instance, then tracing should be disabled or enabled in the instance and
not at the top level, which is confusing to users.

Link: https://lkml.kernel.org/r/20220223223837.14f94ec3@rorschach.local.home

Cc: stable@vger.kernel.org
Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables")
Tested-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 12:06:45 -05:00
Eric W. Biederman
0ac983f512 ucounts: Fix systemd LimitNPROC with private users regression
Long story short recursively enforcing RLIMIT_NPROC when it is not
enforced on the process that creates a new user namespace, causes
currently working code to fail.  There is no reason to enforce
RLIMIT_NPROC recursively when we don't enforce it normally so update
the code to detect this case.

I would like to simply use capable(CAP_SYS_RESOURCE) to detect when
RLIMIT_NPROC is not enforced upon the caller.  Unfortunately because
RLIMIT_NPROC is charged and checked for enforcement based upon the
real uid, using capable() which is euid based is inconsistent with reality.
Come as close as possible to testing for capable(CAP_SYS_RESOURCE) by
testing for when the real uid would match the conditions when
CAP_SYS_RESOURCE would be present if the real uid was the effective
uid.

Reported-by: Etienne Dechamps <etienne@edechamps.fr>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215596
Link: https://lkml.kernel.org/r/e9589141-cfeb-90cd-2d0e-83a62787239a@edechamps.fr
Link: https://lkml.kernel.org/r/87sfs8jmpz.fsf_-_@email.froward.int.ebiederm.org
Cc: stable@vger.kernel.org
Fixes: 21d1c5e386bc ("Reimplement RLIMIT_NPROC on top of ucounts")
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-02-25 10:40:14 -06:00
Daniel Bristot de Oliveira
ce33c845b0 tracing: Dump stacktrace trigger to the corresponding instance
The stacktrace event trigger is not dumping the stacktrace to the instance
where it was enabled, but to the global "instance."

Use the private_data, pointing to the trigger file, to figure out the
corresponding trace instance, and use it in the trigger action, like
snapshot_trigger does.

Link: https://lkml.kernel.org/r/afbb0b4f18ba92c276865bc97204d438473f4ebc.1645396236.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Tested-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-24 22:07:03 -05:00
Jakub Kicinski
aaa25a2fa7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/testing/selftests/net/mptcp/mptcp_join.sh
  34aa6e3bccd8 ("selftests: mptcp: add ip mptcp wrappers")

  857898eb4b28 ("selftests: mptcp: add missing join check")
  6ef84b1517e0 ("selftests: mptcp: more robust signal race test")
https://lore.kernel.org/all/20220221131842.468893-1-broonie@kernel.org/

drivers/net/ethernet/mellanox/mlx5/core/en/tc/act/act.h
drivers/net/ethernet/mellanox/mlx5/core/en/tc/act/ct.c
  fb7e76ea3f3b6 ("net/mlx5e: TC, Skip redundant ct clear actions")
  c63741b426e11 ("net/mlx5e: Fix MPLSoUDP encap to use MPLS action information")

  09bf97923224f ("net/mlx5e: TC, Move pedit_headers_action to parse_attr")
  84ba8062e383 ("net/mlx5e: Test CT and SAMPLE on flow attr")
  efe6f961cd2e ("net/mlx5e: CT, Don't set flow flag CT for ct clear flow")
  3b49a7edec1d ("net/mlx5e: TC, Reject rules with multiple CT actions")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-24 17:54:25 -08:00
Linus Torvalds
f672ff9123 Networking fixes for 5.17-rc6, including fixes from bpf and netfilter.
Current release - regressions:
 
  - bpf: fix crash due to out of bounds access into reg2btf_ids
 
  - mvpp2: always set port pcs ops, avoid null-deref
 
  - eth: marvell: fix driver load from initrd
 
  - eth: intel: revert "Fix reset bw limit when DCB enabled with 1 TC"
 
 Current release - new code bugs:
 
  - mptcp: fix race in overlapping signal events
 
 Previous releases - regressions:
 
  - xen-netback: revert hotplug-status changes causing devices to
    not be configured
 
  - dsa:
    - avoid call to __dev_set_promiscuity() while rtnl_mutex isn't held
    - fix panic when removing unoffloaded port from bridge
 
  - dsa: microchip: fix bridging with more than two member ports
 
 Previous releases - always broken:
 
  - bpf:
   - fix crash due to incorrect copy_map_value when both spin lock
     and timer are present in a single value
   - fix a bpf_timer initialization issue with clang
   - do not try bpf_msg_push_data with len 0
   - add schedule points in batch ops
 
  - nf_tables:
    - unregister flowtable hooks on netns exit
    - correct flow offload action array size
    - fix a couple of memory leaks
 
  - vsock: don't check owner in vhost_vsock_stop() while releasing
 
  - gso: do not skip outer ip header in case of ipip and net_failover
 
  - smc: use a mutex for locking "struct smc_pnettable"
 
  - openvswitch: fix setting ipv6 fields causing hw csum failure
 
  - mptcp: fix race in incoming ADD_ADDR option processing
 
  - sysfs: add check for netdevice being present to speed_show
 
  - sched: act_ct: fix flow table lookup after ct clear or switching
    zones
 
  - eth: intel: fixes for SR-IOV forwarding offloads
 
  - eth: broadcom: fixes for selftests and error recovery
 
  - eth: mellanox: flow steering and SR-IOV forwarding fixes
 
 Misc:
 
  - make __pskb_pull_tail() & pskb_carve_frag_list() drop_monitor
    friends not report freed skbs as drops
 
  - force inlining of checksum functions in net/checksum.h
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Including fixes from bpf and netfilter.

  Current release - regressions:

   - bpf: fix crash due to out of bounds access into reg2btf_ids

   - mvpp2: always set port pcs ops, avoid null-deref

   - eth: marvell: fix driver load from initrd

   - eth: intel: revert "Fix reset bw limit when DCB enabled with 1 TC"

  Current release - new code bugs:

   - mptcp: fix race in overlapping signal events

  Previous releases - regressions:

   - xen-netback: revert hotplug-status changes causing devices to not
     be configured

   - dsa:
      - avoid call to __dev_set_promiscuity() while rtnl_mutex isn't
        held
      - fix panic when removing unoffloaded port from bridge

   - dsa: microchip: fix bridging with more than two member ports

  Previous releases - always broken:

   - bpf:
      - fix crash due to incorrect copy_map_value when both spin lock
        and timer are present in a single value
      - fix a bpf_timer initialization issue with clang
      - do not try bpf_msg_push_data with len 0
      - add schedule points in batch ops

   - nf_tables:
      - unregister flowtable hooks on netns exit
      - correct flow offload action array size
      - fix a couple of memory leaks

   - vsock: don't check owner in vhost_vsock_stop() while releasing

   - gso: do not skip outer ip header in case of ipip and net_failover

   - smc: use a mutex for locking "struct smc_pnettable"

   - openvswitch: fix setting ipv6 fields causing hw csum failure

   - mptcp: fix race in incoming ADD_ADDR option processing

   - sysfs: add check for netdevice being present to speed_show

   - sched: act_ct: fix flow table lookup after ct clear or switching
     zones

   - eth: intel: fixes for SR-IOV forwarding offloads

   - eth: broadcom: fixes for selftests and error recovery

   - eth: mellanox: flow steering and SR-IOV forwarding fixes

  Misc:

   - make __pskb_pull_tail() & pskb_carve_frag_list() drop_monitor
     friends not report freed skbs as drops

   - force inlining of checksum functions in net/checksum.h"

* tag 'net-5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (85 commits)
  net: mv643xx_eth: process retval from of_get_mac_address
  ping: remove pr_err from ping_lookup
  Revert "i40e: Fix reset bw limit when DCB enabled with 1 TC"
  openvswitch: Fix setting ipv6 fields causing hw csum failure
  ipv6: prevent a possible race condition with lifetimes
  net/smc: Use a mutex for locking "struct smc_pnettable"
  bnx2x: fix driver load from initrd
  Revert "xen-netback: Check for hotplug-status existence before watching"
  Revert "xen-netback: remove 'hotplug-status' once it has served its purpose"
  net/mlx5e: Fix VF min/max rate parameters interchange mistake
  net/mlx5e: Add missing increment of count
  net/mlx5e: MPLSoUDP decap, fix check for unsupported matches
  net/mlx5e: Fix MPLSoUDP encap to use MPLS action information
  net/mlx5e: Add feature check for set fec counters
  net/mlx5e: TC, Skip redundant ct clear actions
  net/mlx5e: TC, Reject rules with forward and drop actions
  net/mlx5e: TC, Reject rules with drop and modify hdr action
  net/mlx5e: kTLS, Use CHECKSUM_UNNECESSARY for device-offloaded packets
  net/mlx5e: Fix wrong return value on ioctl EEPROM query failure
  net/mlx5: Fix possible deadlock on rule deletion
  ...
2022-02-24 12:45:32 -08:00
Tom Rix
c561d11063 bpf: Cleanup comments
Add leading space to spdx tag
Use // for spdx c file comment

Replacements
resereved to reserved
inbetween to in between
everytime to every time
intutivie to intuitive
currenct to current
encontered to encountered
referenceing to referencing
upto to up to
exectuted to executed

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220220184055.3608317-1-trix@redhat.com
2022-02-23 15:17:51 -08:00
Linus Torvalds
5c1ee56966 Merge branch 'for-5.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:

 - Fix for a subtle bug in the recent release_agent permission check
   update

 - Fix for a long-standing race condition between cpuset and cpu hotplug

 - Comment updates

* 'for-5.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cpuset: Fix kernel-doc
  cgroup-v1: Correct privileges check in release_agent writes
  cgroup: clarify cgroup_css_set_fork()
  cgroup/cpuset: Fix a race between cpuset_attach() and cpu hotplug
2022-02-22 16:14:35 -08:00
Jiapeng Chong
c70cd039f1 cpuset: Fix kernel-doc
Fix the following W=1 kernel warnings:

kernel/cgroup/cpuset.c:3718: warning: expecting prototype for
cpuset_memory_pressure_bump(). Prototype was for
__cpuset_memory_pressure_bump() instead.

kernel/cgroup/cpuset.c:3568: warning: expecting prototype for
cpuset_node_allowed(). Prototype was for __cpuset_node_allowed()
instead.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2022-02-22 09:49:49 -10:00
Michal Koutný
467a726b75 cgroup-v1: Correct privileges check in release_agent writes
The idea is to check: a) the owning user_ns of cgroup_ns, b)
capabilities in init_user_ns.

The commit 24f600856418 ("cgroup-v1: Require capabilities to set
release_agent") got this wrong in the write handler of release_agent
since it checked user_ns of the opener (may be different from the owning
user_ns of cgroup_ns).
Secondly, to avoid possibly confused deputy, the capability of the
opener must be checked.

Fixes: 24f600856418 ("cgroup-v1: Require capabilities to set release_agent")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/stable/20220216121142.GB30035@blackbody.suse.cz/
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Masami Ichikawa(CIP) <masami.ichikawa@cybertrust.co.jp>
Signed-off-by: Tejun Heo <tj@kernel.org>
2022-02-22 08:12:22 -10:00
Christian Brauner
6d3971dab2 cgroup: clarify cgroup_css_set_fork()
With recent fixes for the permission checking when moving a task into a cgroup
using a file descriptor to a cgroup's cgroup.procs file and calling write() it
seems a good idea to clarify CLONE_INTO_CGROUP permission checking with a
comment.

Cc: Tejun Heo <tj@kernel.org>
Cc: <cgroups@vger.kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2022-02-22 07:35:19 -10:00
Linus Torvalds
3324e6e803 - Fix a NULL ptr dereference when dumping lockdep chains through /proc/lockdep_chains
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Merge tag 'locking_urgent_for_v5.17_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fix from Borislav Petkov:
 "Fix a NULL ptr dereference when dumping lockdep chains through
  /proc/lockdep_chains"

* tag 'locking_urgent_for_v5.17_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep: Correct lock_classes index mapping
2022-02-20 12:50:50 -08:00
Linus Torvalds
0b0894ff78 - Fix task exposure order when forking tasks
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Merge tag 'sched_urgent_for_v5.17_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fix from Borislav Petkov:
 "Fix task exposure order when forking tasks"

* tag 'sched_urgent_for_v5.17_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix yet more sched_fork() races
2022-02-20 12:40:20 -08:00
Linus Torvalds
c1034d249d pidfd.v5.17-rc4
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Merge tag 'pidfd.v5.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull pidfd fix from Christian Brauner:
 "This fixes a problem reported by lockdep when installing a pidfd via
  fd_install() with siglock and the tasklisk write lock held in
  copy_process() when calling clone()/clone3() with CLONE_PIDFD.

  Originally a pidfd was created prior to holding any of these locks but
  this required a call to ksys_close(). So quite some time ago in
  6fd2fe494b17 ("copy_process(): don't use ksys_close() on cleanups") we
  switched to a get_unused_fd_flags() + fd_install() model.

  As part of that we moved fd_install() as late as possible. This was
  done for two main reasons. First, because we needed to ensure that we
  call fd_install() past the point of no return as once that's called
  the fd is live in the task's file table. Second, because we tried to
  ensure that the fd is visible in /proc/<pid>/fd/<pidfd> right when the
  task is visible.

  This fix moves the fd_install() to an even later point which means
  that a task will be visible in proc while the pidfd isn't yet under
  /proc/<pid>/fd/<pidfd>.

  While this is a user visible change it's very unlikely that this will
  have any impact. Nobody should be relying on that and if they do we
  need to come up with something better but again, it's doubtful this is
  relevant"

* tag 'pidfd.v5.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  copy_process(): Move fd_install() out of sighand->siglock critical section
2022-02-20 10:55:05 -08:00
Linus Torvalds
2d3409ebc8 Merge branch 'ucount-rlimit-fixes-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull ucounts fixes from Eric Biederman:
 "Michal Koutný recently found some bugs in the enforcement of
  RLIMIT_NPROC in the recent ucount rlimit implementation.

  In this set of patches I have developed a very conservative approach
  changing only what is necessary to fix the bugs that I can see
  clearly. Cleanups and anything that is making the code more consistent
  can follow after we have the code working as it has historically.

  The problem is not so much inconsistencies (although those exist) but
  that it is very difficult to figure out what the code should be doing
  in the case of RLIMIT_NPROC.

  All other rlimits are only enforced where the resource is acquired
  (allocated). RLIMIT_NPROC by necessity needs to be enforced in an
  additional location, and our current implementation stumbled it's way
  into that implementation"

* 'ucount-rlimit-fixes-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ucounts: Handle wrapping in is_ucounts_overlimit
  ucounts: Move RLIMIT_NPROC handling after set_user
  ucounts: Base set_cred_ucounts changes on the real user
  ucounts: Enforce RLIMIT_NPROC not RLIMIT_NPROC+1
  rlimit: Fix RLIMIT_NPROC enforcement failure caused by capability calls in set_user
2022-02-20 10:44:11 -08:00
Souptick Joarder (HPE)
d0b3822902 bpf: Initialize ret to 0 inside btf_populate_kfunc_set()
Kernel test robot reported below error ->

kernel/bpf/btf.c:6718 btf_populate_kfunc_set()
error: uninitialized symbol 'ret'.

Initialize ret to 0.

Fixes: dee872e124e8 ("bpf: Populate kfunc BTF ID sets in struct btf")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Souptick Joarder (HPE) <jrdr.linux@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/bpf/20220219163915.125770-1-jrdr.linux@gmail.com
2022-02-19 17:26:52 -08:00
Peter Zijlstra
b1e8206582 sched: Fix yet more sched_fork() races
Where commit 4ef0c5c6b5ba ("kernel/sched: Fix sched_fork() access an
invalid sched_task_group") fixed a fork race vs cgroup, it opened up a
race vs syscalls by not placing the task on the runqueue before it
gets exposed through the pidhash.

Commit 13765de8148f ("sched/fair: Fix fault in reweight_entity") is
trying to fix a single instance of this, instead fix the whole class
of issues, effectively reverting this commit.

Fixes: 4ef0c5c6b5ba ("kernel/sched: Fix sched_fork() access an invalid sched_task_group")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Tested-by: Zhang Qiao <zhangqiao22@huawei.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lkml.kernel.org/r/YgoeCbwj5mbCR0qA@hirez.programming.kicks-ass.net
2022-02-19 11:11:05 +01:00
Eric Dumazet
9087c6ff8d bpf: Call maybe_wait_bpf_programs() only once from generic_map_delete_batch()
As stated in the comment found in maybe_wait_bpf_programs(),
the synchronize_rcu() barrier is only needed before returning
to userspace, not after each deletion in the batch.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20220218181801.2971275-1-eric.dumazet@gmail.com
2022-02-18 20:37:26 +01:00
Jakub Kicinski
a3fc4b1d09 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
bpf-next 2022-02-17

We've added 29 non-merge commits during the last 8 day(s) which contain
a total of 34 files changed, 1502 insertions(+), 524 deletions(-).

The main changes are:

1) Add BTFGen support to bpftool which allows to use CO-RE in kernels without
   BTF info, from Mauricio Vásquez, Rafael David Tinoco, Lorenzo Fontana and
   Leonardo Di Donato. (Details: https://lpc.events/event/11/contributions/948/)

2) Prepare light skeleton to be used in both kernel module and user space
   and convert bpf_preload.ko to use light skeleton, from Alexei Starovoitov.

3) Rework bpftool's versioning scheme and align with libbpf's version number;
   also add linked libbpf version info to "bpftool version", from Quentin Monnet.

4) Add minimal C++ specific additions to bpftool's skeleton codegen to
   facilitate use of C skeletons in C++ applications, from Andrii Nakryiko.

5) Add BPF verifier sanity check whether relative offset on kfunc calls overflows
   desc->imm and reject the BPF program if the case, from Hou Tao.

6) Fix libbpf to use a dynamically allocated buffer for netlink messages to
   avoid receiving truncated messages on some archs, from Toke Høiland-Jørgensen.

7) Various follow-up fixes to the JIT bpf_prog_pack allocator, from Song Liu.

8) Various BPF selftest and vmtest.sh fixes, from Yucong Sun.

9) Fix bpftool pretty print handling on dumping map keys/values when no BTF
   is available, from Jiri Olsa and Yinjun Zhang.

10) Extend XDP frags selftest to check for invalid length, from Lorenzo Bianconi.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (29 commits)
  bpf: bpf_prog_pack: Set proper size before freeing ro_header
  selftests/bpf: Fix crash in core_reloc when bpftool btfgen fails
  selftests/bpf: Fix vmtest.sh to launch smp vm.
  libbpf: Fix memleak in libbpf_netlink_recv()
  bpftool: Fix C++ additions to skeleton
  bpftool: Fix pretty print dump for maps without BTF loaded
  selftests/bpf: Test "bpftool gen min_core_btf"
  bpftool: Gen min_core_btf explanation and examples
  bpftool: Implement btfgen_get_btf()
  bpftool: Implement "gen min_core_btf" logic
  bpftool: Add gen min_core_btf command
  libbpf: Expose bpf_core_{add,free}_cands() to bpftool
  libbpf: Split bpf_core_apply_relo()
  bpf: Reject kfunc calls that overflow insn->imm
  selftests/bpf: Add Skeleton templated wrapper as an example
  bpftool: Add C++-specific open/load/etc skeleton wrappers
  selftests/bpf: Fix GCC11 compiler warnings in -O2 mode
  bpftool: Fix the error when lookup in no-btf maps
  libbpf: Use dynamically allocated buffer when receiving netlink messages
  libbpf: Fix libbpf.map inheritance chain for LIBBPF_0.7.0
  ...
====================

Link: https://lore.kernel.org/r/20220217232027.29831-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 17:23:52 -08:00
Song Liu
d24d2a2b0a bpf: bpf_prog_pack: Set proper size before freeing ro_header
bpf_prog_pack_free() uses header->size to decide whether the header
should be freed with module_memfree() or the bpf_prog_pack logic.
However, in kvmalloc() failure path of bpf_jit_binary_pack_alloc(),
header->size is not set yet. As a result, bpf_prog_pack_free() may treat
a slice of a pack as a standalone kvmalloc'd header and call
module_memfree() on the whole pack. This in turn causes use-after-free by
other users of the pack.

Fix this by setting ro_header->size before freeing ro_header.

Fixes: 33c9805860e5 ("bpf: Introduce bpf_jit_binary_pack_[alloc|finalize|free]")
Reported-by: syzbot+2f649ec6d2eea1495a8f@syzkaller.appspotmail.com
Reported-by: syzbot+ecb1e7e51c52f68f7481@syzkaller.appspotmail.com
Reported-by: syzbot+87f65c75f4a72db05445@syzkaller.appspotmail.com
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220217183001.1876034-1-song@kernel.org
2022-02-17 13:15:36 -08:00
Jakub Kicinski
93d11e0d76 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Fast path bpf marge for some -next work.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 12:22:28 -08:00
Jakub Kicinski
7a2fb91285 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says:

====================
pull-request: bpf 2022-02-17

We've added 8 non-merge commits during the last 7 day(s) which contain
a total of 8 files changed, 119 insertions(+), 15 deletions(-).

The main changes are:

1) Add schedule points in map batch ops, from Eric.

2) Fix bpf_msg_push_data with len 0, from Felix.

3) Fix crash due to incorrect copy_map_value, from Kumar.

4) Fix crash due to out of bounds access into reg2btf_ids, from Kumar.

5) Fix a bpf_timer initialization issue with clang, from Yonghong.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Add schedule points in batch ops
  bpf: Fix crash due to out of bounds access into reg2btf_ids.
  selftests: bpf: Check bpf_msg_push_data return value
  bpf: Fix a bpf_timer initialization issue
  bpf: Emit bpf_timer in vmlinux BTF
  selftests/bpf: Add test for bpf_timer overwriting crash
  bpf: Fix crash due to incorrect copy_map_value
  bpf: Do not try bpf_msg_push_data with len 0
====================

Link: https://lore.kernel.org/r/20220217190000.37925-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 12:01:55 -08:00
Jakub Kicinski
6b5567b1b2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 11:44:20 -08:00
Eric Dumazet
75134f16e7 bpf: Add schedule points in batch ops
syzbot reported various soft lockups caused by bpf batch operations.

 INFO: task kworker/1:1:27 blocked for more than 140 seconds.
 INFO: task hung in rcu_barrier

Nothing prevents batch ops to process huge amount of data,
we need to add schedule points in them.

Note that maybe_wait_bpf_programs(map) calls from
generic_map_delete_batch() can be factorized by moving
the call after the loop.

This will be done later in -next tree once we get this fix merged,
unless there is strong opinion doing this optimization sooner.

Fixes: aa2e93b8e58e ("bpf: Add generic support for update and delete batch ops")
Fixes: cb4d03ab499d ("bpf: Add generic support for lookup batch op")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Brian Vazquez <brianvv@google.com>
Link: https://lore.kernel.org/bpf/20220217181902.808742-1-eric.dumazet@gmail.com
2022-02-17 10:48:26 -08:00
Eric W. Biederman
0cbae9e24f ucounts: Handle wrapping in is_ucounts_overlimit
While examining is_ucounts_overlimit and reading the various messages
I realized that is_ucounts_overlimit fails to deal with counts that
may have wrapped.

Being wrapped should be a transitory state for counts and they should
never be wrapped for long, but it can happen so handle it.

Cc: stable@vger.kernel.org
Fixes: 21d1c5e386bc ("Reimplement RLIMIT_NPROC on top of ucounts")
Link: https://lkml.kernel.org/r/20220216155832.680775-5-ebiederm@xmission.com
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-02-17 09:11:57 -06:00
Eric W. Biederman
c923a8e7ed ucounts: Move RLIMIT_NPROC handling after set_user
During set*id() which cred->ucounts to charge the the current process
to is not known until after set_cred_ucounts.  So move the
RLIMIT_NPROC checking into a new helper flag_nproc_exceeded and call
flag_nproc_exceeded after set_cred_ucounts.

This is very much an arbitrary subset of the places where we currently
change the RLIMIT_NPROC accounting, designed to preserve the existing
logic.

Fixing the existing logic will be the subject of another series of
changes.

Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20220216155832.680775-4-ebiederm@xmission.com
Fixes: 21d1c5e386bc ("Reimplement RLIMIT_NPROC on top of ucounts")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-02-17 09:11:26 -06:00
Eric W. Biederman
a55d07294f ucounts: Base set_cred_ucounts changes on the real user
Michal Koutný <mkoutny@suse.com> wrote:
> Tasks are associated to multiple users at once. Historically and as per
> setrlimit(2) RLIMIT_NPROC is enforce based on real user ID.
>
> The commit 21d1c5e386bc ("Reimplement RLIMIT_NPROC on top of ucounts")
> made the accounting structure "indexed" by euid and hence potentially
> account tasks differently.
>
> The effective user ID may be different e.g. for setuid programs but
> those are exec'd into already existing task (i.e. below limit), so
> different accounting is moot.
>
> Some special setresuid(2) users may notice the difference, justifying
> this fix.

I looked at cred->ucount and it is only used for rlimit operations
that were previously stored in cred->user.  Making the fact
cred->ucount can refer to a different user from cred->user a bug,
affecting all uses of cred->ulimit not just RLIMIT_NPROC.

Fix set_cred_ucounts to always use the real uid not the effective uid.

Further simplify set_cred_ucounts by noticing that set_cred_ucounts
somehow retained a draft version of the check to see if alloc_ucounts
was needed that checks the new->user and new->user_ns against the
current_real_cred().  Remove that draft version of the check.

All that matters for setting the cred->ucounts are the user_ns and uid
fields in the cred.

Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20220207121800.5079-4-mkoutny@suse.com
Link: https://lkml.kernel.org/r/20220216155832.680775-3-ebiederm@xmission.com
Reported-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Fixes: 21d1c5e386bc ("Reimplement RLIMIT_NPROC on top of ucounts")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-02-17 09:11:02 -06:00
Eric W. Biederman
8f2f9c4d82 ucounts: Enforce RLIMIT_NPROC not RLIMIT_NPROC+1
Michal Koutný <mkoutny@suse.com> wrote:

> It was reported that v5.14 behaves differently when enforcing
> RLIMIT_NPROC limit, namely, it allows one more task than previously.
> This is consequence of the commit 21d1c5e386bc ("Reimplement
> RLIMIT_NPROC on top of ucounts") that missed the sharpness of
> equality in the forking path.

This can be fixed either by fixing the test or by moving the increment
to be before the test.  Fix it my moving copy_creds which contains
the increment before is_ucounts_overlimit.

In the case of CLONE_NEWUSER the ucounts in the task_cred changes.
The function is_ucounts_overlimit needs to use the final version of
the ucounts for the new process.  Which means moving the
is_ucounts_overlimit test after copy_creds is necessary.

Both the test in fork and the test in set_user were semantically
changed when the code moved to ucounts.  The change of the test in
fork was bad because it was before the increment.  The test in
set_user was wrong and the change to ucounts fixed it.  So this
fix only restores the old behavior in one lcation not two.

Link: https://lkml.kernel.org/r/20220204181144.24462-1-mkoutny@suse.com
Link: https://lkml.kernel.org/r/20220216155832.680775-2-ebiederm@xmission.com
Cc: stable@vger.kernel.org
Reported-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Fixes: 21d1c5e386bc ("Reimplement RLIMIT_NPROC on top of ucounts")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-02-17 09:10:33 -06:00
Eric W. Biederman
c16bdeb5a3 rlimit: Fix RLIMIT_NPROC enforcement failure caused by capability calls in set_user
Solar Designer <solar@openwall.com> wrote:
> I'm not aware of anyone actually running into this issue and reporting
> it.  The systems that I personally know use suexec along with rlimits
> still run older/distro kernels, so would not yet be affected.
>
> So my mention was based on my understanding of how suexec works, and
> code review.  Specifically, Apache httpd has the setting RLimitNPROC,
> which makes it set RLIMIT_NPROC:
>
> https://httpd.apache.org/docs/2.4/mod/core.html#rlimitnproc
>
> The above documentation for it includes:
>
> "This applies to processes forked from Apache httpd children servicing
> requests, not the Apache httpd children themselves. This includes CGI
> scripts and SSI exec commands, but not any processes forked from the
> Apache httpd parent, such as piped logs."
>
> In code, there are:
>
> ./modules/generators/mod_cgid.c:        ( (cgid_req.limits.limit_nproc_set) && ((rc = apr_procattr_limit_set(procattr, APR_LIMIT_NPROC,
> ./modules/generators/mod_cgi.c:        ((rc = apr_procattr_limit_set(procattr, APR_LIMIT_NPROC,
> ./modules/filters/mod_ext_filter.c:    rv = apr_procattr_limit_set(procattr, APR_LIMIT_NPROC, conf->limit_nproc);
>
> For example, in mod_cgi.c this is in run_cgi_child().
>
> I think this means an httpd child sets RLIMIT_NPROC shortly before it
> execs suexec, which is a SUID root program.  suexec then switches to the
> target user and execs the CGI script.
>
> Before 2863643fb8b9, the setuid() in suexec would set the flag, and the
> target user's process count would be checked against RLIMIT_NPROC on
> execve().  After 2863643fb8b9, the setuid() in suexec wouldn't set the
> flag because setuid() is (naturally) called when the process is still
> running as root (thus, has those limits bypass capabilities), and
> accordingly execve() would not check the target user's process count
> against RLIMIT_NPROC.

In commit 2863643fb8b9 ("set_user: add capability check when
rlimit(RLIMIT_NPROC) exceeds") capable calls were added to set_user to
make it more consistent with fork.  Unfortunately because of call site
differences those capable calls were checking the credentials of the
user before set*id() instead of after set*id().

This breaks enforcement of RLIMIT_NPROC for applications that set the
rlimit and then call set*id() while holding a full set of
capabilities.  The capabilities are only changed in the new credential
in security_task_fix_setuid().

The code in apache suexec appears to follow this pattern.

Commit 909cc4ae86f3 ("[PATCH] Fix two bugs with process limits
(RLIMIT_NPROC)") where this check was added describes the targes of this
capability check as:

  2/ When a root-owned process (e.g. cgiwrap) sets up process limits and then
      calls setuid, the setuid should fail if the user would then be running
      more than rlim_cur[RLIMIT_NPROC] processes, but it doesn't.  This patch
      adds an appropriate test.  With this patch, and per-user process limit
      imposed in cgiwrap really works.

So the original use case of this check also appears to match the broken
pattern.

Restore the enforcement of RLIMIT_NPROC by removing the bad capable
checks added in set_user.  This unfortunately restores the
inconsistent state the code has been in for the last 11 years, but
dealing with the inconsistencies looks like a larger problem.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20210907213042.GA22626@openwall.com/
Link: https://lkml.kernel.org/r/20220212221412.GA29214@openwall.com
Link: https://lkml.kernel.org/r/20220216155832.680775-1-ebiederm@xmission.com
Fixes: 2863643fb8b9 ("set_user: add capability check when rlimit(RLIMIT_NPROC) exceeds")
History-Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Reviewed-by: Solar Designer <solar@openwall.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-02-17 09:08:05 -06:00
Dmitry Torokhov
a8e8f851e8 module: fix building with sysfs disabled
Sysfs support might be disabled so we need to guard the code that
instantiates "compression" attribute with an #ifdef.

Fixes: b1ae6dc41eaa ("module: add in-kernel support for decompressing")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2022-02-16 12:51:32 -08:00
Kumar Kartikeya Dwivedi
45ce4b4f90 bpf: Fix crash due to out of bounds access into reg2btf_ids.
When commit e6ac2450d6de ("bpf: Support bpf program calling kernel function") added
kfunc support, it defined reg2btf_ids as a cheap way to translate the verifier
reg type to the appropriate btf_vmlinux BTF ID, however
commit c25b2ae13603 ("bpf: Replace PTR_TO_XXX_OR_NULL with PTR_TO_XXX | PTR_MAYBE_NULL")
moved the __BPF_REG_TYPE_MAX from the last member of bpf_reg_type enum to after
the base register types, and defined other variants using type flag
composition. However, now, the direct usage of reg->type to index into
reg2btf_ids may no longer fall into __BPF_REG_TYPE_MAX range, and hence lead to
out of bounds access and kernel crash on dereference of bad pointer.

Fixes: c25b2ae13603 ("bpf: Replace PTR_TO_XXX_OR_NULL with PTR_TO_XXX | PTR_MAYBE_NULL")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220216201943.624869-1-memxor@gmail.com
2022-02-16 12:46:51 -08:00
Mauricio Vásquez
adb8fa195e libbpf: Split bpf_core_apply_relo()
BTFGen needs to run the core relocation logic in order to understand
what are the types involved in a given relocation.

Currently bpf_core_apply_relo() calculates and **applies** a relocation
to an instruction. Having both operations in the same function makes it
difficult to only calculate the relocation without patching the
instruction. This commit splits that logic in two different phases: (1)
calculate the relocation and (2) patch the instruction.

For the first phase bpf_core_apply_relo() is renamed to
bpf_core_calc_relo_insn() who is now only on charge of calculating the
relocation, the second phase uses the already existing
bpf_core_patch_insn(). bpf_object__relocate_core() uses both of them and
the BTFGen will use only bpf_core_calc_relo_insn().

Signed-off-by: Mauricio Vásquez <mauricio@kinvolk.io>
Signed-off-by: Rafael David Tinoco <rafael.tinoco@aquasec.com>
Signed-off-by: Lorenzo Fontana <lorenzo.fontana@elastic.co>
Signed-off-by: Leonardo Di Donato <leonardo.didonato@elastic.co>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220215225856.671072-2-mauricio@kinvolk.io
2022-02-16 10:05:42 -08:00
Hou Tao
8cbf062a25 bpf: Reject kfunc calls that overflow insn->imm
Now kfunc call uses s32 to represent the offset between the address of
kfunc and __bpf_call_base, but it doesn't check whether or not s32 will
be overflowed. The overflow is possible when kfunc is in module and the
offset between module and kernel is greater than 2GB. Take arm64 as an
example, before commit b2eed9b58811 ("arm64/kernel: kaslr: reduce module
randomization range to 2 GB"), the offset between module symbol and
__bpf_call_base will in 4GB range due to KASLR and may overflow s32.

So add an extra checking to reject these invalid kfunc calls.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220215065732.3179408-1-houtao1@huawei.com
2022-02-15 10:05:11 -08:00
Zhang Qiao
05c7b7a92c cgroup/cpuset: Fix a race between cpuset_attach() and cpu hotplug
As previously discussed(https://lkml.org/lkml/2022/1/20/51),
cpuset_attach() is affected with similar cpu hotplug race,
as follow scenario:

     cpuset_attach()				cpu hotplug
    ---------------------------            ----------------------
    down_write(cpuset_rwsem)
    guarantee_online_cpus() // (load cpus_attach)
					sched_cpu_deactivate
					  set_cpu_active()
					  // will change cpu_active_mask
    set_cpus_allowed_ptr(cpus_attach)
      __set_cpus_allowed_ptr_locked()
       // (if the intersection of cpus_attach and
         cpu_active_mask is empty, will return -EINVAL)
    up_write(cpuset_rwsem)

To avoid races such as described above, protect cpuset_attach() call
with cpu_hotplug_lock.

Fixes: be367d099270 ("cgroups: let ss->can_attach and ss->attach do whole threadgroups at a time")
Cc: stable@vger.kernel.org # v2.6.32+
Reported-by: Zhao Gongyi <zhaogongyi@huawei.com>
Signed-off-by: Zhang Qiao <zhangqiao22@huawei.com>
Acked-by: Waiman Long <longman@redhat.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2022-02-14 09:48:04 -10:00