bpf: Fix WARN() in get_bpf_raw_tp_regs

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix WARN() in get_bpf_raw_tp_regs syzkaller reported an issue: WARNING: CPU: 3 PID: 5971 at kernel/trace/bpf_trace.c:1861 get_bpf_raw_tp_regs+0xa4/0x100 kernel/trace/bpf_trace.c:1861 Modules linked in: CPU: 3 UID: 0 PID: 5971 Comm: syz-executor205 Not tainted 6.15.0-rc5-syzkaller-00038-g707df3375124 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:get_bpf_raw_tp_regs+0xa4/0x100 kernel/trace/bpf_trace.c:1861 RSP: 0018:ffffc90003636fa8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000003 RCX: ffffffff81c6bc4c RDX: ffff888032efc880 RSI: ffffffff81c6bc83 RDI: 0000000000000005 RBP: ffff88806a730860 R08: 0000000000000005 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000004 R13: 0000000000000001 R14: ffffc90003637008 R15: 0000000000000900 FS: 0000000000000000(0000) GS:ffff8880d6cdf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7baee09130 CR3: 0000000029f5a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1934 [inline] bpf_get_stack_raw_tp+0x24/0x160 kernel/trace/bpf_trace.c:1931 bpf_prog_ec3b2eefa702d8d3+0x43/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2363 [inline] bpf_trace_run3+0x23f/0x5a0 kernel/trace/bpf_trace.c:2405 __bpf_trace_mmap_lock_acquire_returned+0xfc/0x140 include/trace/events/mmap_lock.h:47 __traceiter_mmap_lock_acquire_returned+0x79/0xc0 include/trace/events/mmap_lock.h:47 __do_trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:47 [inline] trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:47 [inline] __mmap_lock_do_trace_acquire_returned+0x138/0x1f0 mm/mmap_lock.c:35 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:204 [inline] stack_map_get_build_id_offset+0x535/0x6f0 kernel/bpf/stackmap.c:157 __bpf_get_stack+0x307/0xa10 kernel/bpf/stackmap.c:483 ____bpf_get_stack kernel/bpf/stackmap.c:499 [inline] bpf_get_stack+0x32/0x40 kernel/bpf/stackmap.c:496 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1941 [inline] bpf_get_stack_raw_tp+0x124/0x160 kernel/trace/bpf_trace.c:1931 bpf_prog_ec3b2eefa702d8d3+0x43/0x47 Tracepoint like trace_mmap_lock_acquire_returned may cause nested call as the corner case show above, which will be resolved with more general method in the future. As a result, WARN_ON_ONCE will be triggered. As Alexei suggested, remove the WARN_ON_ONCE first.

Timeline

1. Jul 10, 2025, 7:42 AM UTCCVE published
2. Oct 15, 2026, 1:07 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 9594dc3c7e71b9f52bee1d7852eb3d4e3aea9e99 · fixed in 44ebe361abb322d2afd77930fa767a99f271c4d1; From 9594dc3c7e71b9f52bee1d7852eb3d4e3aea9e99 · fixed in 147ea936fc6fa8fe0c93f0df918803a5375ca535; From 9594dc3c7e71b9f52bee1d7852eb3d4e3aea9e99 · fixed in ee90be48edb3dac612e0b7f5332482a9e8be2696; From 9594dc3c7e71b9f52bee1d7852eb3d4e3aea9e99 · fixed in e167414beabb1e941fe563a96becc98627d5bdf6; From 9594dc3c7e71b9f52bee1d7852eb3d4e3aea9e99 · fixed in 6d8f39875a10a194051c3eaefebc7ac06a34aaf3; From 9594dc3c7e71b9f52bee1d7852eb3d4e3aea9e99 · fixed in c98cdf6795a36bca163ebb40411fef1687b9eb13; From 9594dc3c7e71b9f52bee1d7852eb3d4e3aea9e99 · fixed in 18e8cbbae79cb35bdce8a01c889827b9799c762e; From 9594dc3c7e71b9f52bee1d7852eb3d4e3aea9e99 · fixed in 3880cdbed1c4607e378f58fa924c5d6df900d1d3; From 4.19.57 · fixed in 4.20; From 5.1.16 · fixed in 5.2

• Linux Linux

  5.2

• KernelLinux

  From 5.2.0 · fixed in 5.4.295; From 5.5.0 · fixed in 5.10.239; From 5.11.0 · fixed in 5.15.186; From 5.16.0 · fixed in 6.1.142; From 6.2.0 · fixed in 6.6.94; From 6.7.0 · fixed in 6.12.34; From 6.13.0 · fixed in 6.15.3

References 8