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KMSAN: uninit-value in __seccomp_filter (2)

Status: closed as invalid on 2020/07/22 14:22
Subsystems: bpf
[Documentation on labels]
First crash: 1350d, last: 1347d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in __seccomp_filter bpf 2 1400d 1400d 0/26 closed as invalid on 2020/05/28 10:53

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in __seccomp_filter+0x10bc/0x2720 kernel/seccomp.c:821
CPU: 1 PID: 8491 Comm: syz-executor935 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1df/0x240 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 __seccomp_filter+0x10bc/0x2720 kernel/seccomp.c:821
 __secure_computing+0x1fa/0x380 kernel/seccomp.c:950
 syscall_trace_enter+0x63b/0xe10 arch/x86/entry/common.c:194
 do_syscall_64+0x54/0x150 arch/x86/entry/common.c:382
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x43eea8
Code: Bad RIP value.
RSP: 002b:00007ffc31d98e08 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043eea8
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004be6a8 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d0180 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 ___bpf_prog_run+0x2b37/0x97a0 kernel/bpf/core.c:1412
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:556 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:597 [inline]
 seccomp_run_filters kernel/seccomp.c:272 [inline]
 __seccomp_filter+0x59e/0x2720 kernel/seccomp.c:817
 __secure_computing+0x1fa/0x380 kernel/seccomp.c:950
 syscall_trace_enter+0x63b/0xe10 arch/x86/entry/common.c:194
 do_syscall_64+0x54/0x150 arch/x86/entry/common.c:382
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 ___bpf_prog_run+0x6c64/0x97a0 kernel/bpf/core.c:1391
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:556 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:597 [inline]
 seccomp_run_filters kernel/seccomp.c:272 [inline]
 __seccomp_filter+0x59e/0x2720 kernel/seccomp.c:817
 __secure_computing+0x1fa/0x380 kernel/seccomp.c:950
 syscall_trace_enter+0x63b/0xe10 arch/x86/entry/common.c:194
 do_syscall_64+0x54/0x150 arch/x86/entry/common.c:382
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Local variable ----regs@__bpf_prog_run32 created at:
 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681
 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681
=====================================================

Crashes (29):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/07/20 04:33 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report syz C ci-upstream-kmsan-gce
2020/07/20 10:34 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/20 09:57 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/19 23:45 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/19 23:35 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/19 21:25 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 20:39 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 20:19 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 09:51 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 08:42 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 07:18 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 06:57 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 05:20 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 02:46 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 01:54 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 01:11 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/17 23:11 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/17 23:00 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/17 22:22 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/17 21:02 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/17 20:31 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/17 18:57 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/17 18:13 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce
2020/07/18 13:02 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce-386
2020/07/18 00:34 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce-386
2020/07/18 00:14 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce-386
2020/07/17 21:55 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce-386
2020/07/17 20:52 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce-386
2020/07/17 18:05 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config console log report ci-upstream-kmsan-gce-386
* Struck through repros no longer work on HEAD.