BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu

Status: upstream: reported C repro on 2026/06/30 06:20
Subsystems: bpf
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+fd7e415d891073b83e1f@syzkaller.appspotmail.com
First crash: 40d, last: 1h32m
Cause bisection: failed (error log, bisect log)
  
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
988973dd assessment-security DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu 2026/06/19 00:08 2026/06/19 00:08 2026/06/19 01:00 24486521

			
		
Discussions (4)
Title Replies (including bot) Last reply
[syzbot] Monthly bpf report (Jul 2026) 0 (1) 2026/07/23 04:32
[PATCH v3] bpf: Fix smp_processor_id() call trace for preemptible kernels 9 (9) 2026/07/02 05:40
[syzbot] [bpf?] BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu 3 (7) 2026/06/30 11:22
[PATCH] bpf: Fix smp_processor_id() call trace for preemptible kernels 4 (4) 2026/06/30 09:48
Last patch testing requests (3)
Created Duration User Patch Repo Result
2026/06/30 09:08 27m eadavis@qq.com patch bpf log
2026/06/30 08:20 27m eadavis@qq.com patch bpf log
2026/06/30 08:17 40m eadavis@qq.com patch bpf log

Sample crash report:
BUG: using smp_processor_id() in preemptible [00000000] code: syz.0.17/5933
caller is bpf_mem_cache_free_rcu+0x41/0xb0 kernel/bpf/memalloc.c:954
CPU: 3 UID: 0 PID: 5933 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 check_preemption_disabled+0xd8/0xe0 lib/smp_processor_id.c:47
 bpf_mem_cache_free_rcu+0x41/0xb0 kernel/bpf/memalloc.c:954
 rhtab_delete_elem+0x96f/0x24e0 kernel/bpf/hashtab.c:2969
 __rhtab_map_lookup_and_delete_batch+0x925/0xf40 kernel/bpf/hashtab.c:3349
 bpf_map_do_batch+0x2b2/0x6d0 kernel/bpf/syscall.c:5830
 __sys_bpf+0xeb8/0x4e80 kernel/bpf/syscall.c:6483
 __do_sys_bpf kernel/bpf/syscall.c:6537 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6534 [inline]
 __x64_sys_bpf+0xce/0x140 kernel/bpf/syscall.c:6534
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f33aab9de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff79abbf18 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f33aae25fa0 RCX: 00007f33aab9de59
RDX: 0000000000000038 RSI: 00002000000018c0 RDI: 0000000000000019
RBP: 00007f33aac33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f33aae25fac R14: 00007f33aae25fa0 R15: 00007f33aae25fa0
 </TASK>

Crashes (1423):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/09 08:12 upstream 0e35b9b6ec0f b9f1ceaa .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/18 01:57 bpf e771677c937d b62b3ded .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/18 01:28 bpf e771677c937d b62b3ded .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/18 01:59 bpf-next 66affa37cfac b62b3ded .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/28 21:10 upstream 8b69c0475871 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/25 19:21 upstream ab9de95c9cf9 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/21 06:15 upstream 1a3746ccbb0a 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/20 13:49 upstream 1a3746ccbb0a 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/19 01:46 upstream 9e7e66334583 a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/28 01:07 upstream 62cc90241548 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 20:09 upstream f5098b6bae76 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 18:47 upstream f5098b6bae76 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 16:18 upstream f5098b6bae76 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 13:17 upstream f5098b6bae76 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 12:12 upstream f5098b6bae76 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 10:31 upstream f5098b6bae76 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 09:24 upstream 4235cb24ec1e 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 08:45 upstream 4235cb24ec1e 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 06:39 upstream 4235cb24ec1e 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 05:22 upstream 4235cb24ec1e 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 02:43 upstream 4235cb24ec1e 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 00:21 upstream 4235cb24ec1e 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 22:18 upstream 4235cb24ec1e 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 21:15 upstream 4235cb24ec1e 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 19:57 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 18:38 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 15:57 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 14:10 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 13:49 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 11:16 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 09:10 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 07:37 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 05:09 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 01:08 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 22:47 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 21:15 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 20:59 upstream 3dab139d4795 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 16:43 upstream 0ce37745d4bf 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 15:19 upstream 0ce37745d4bf 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 14:52 upstream 0ce37745d4bf 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 13:20 upstream 0ce37745d4bf 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 12:09 upstream 0ce37745d4bf 4a865b71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/20 13:56 upstream 1a3746ccbb0a 43bfcdb0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/28 00:04 bpf 0ce37745d4bf 4cb2b096 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 04:01 bpf 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 23:00 bpf 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 12:30 bpf 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 10:13 bpf 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 06:34 bpf 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/24 06:21 net 78f75d632f74 544adce9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/27 21:11 bpf-next 4748a67f7111 4cb2b096 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 17:31 bpf-next 4748a67f7111 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 02:45 bpf-next 4748a67f7111 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/26 00:04 bpf-next 4748a67f7111 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 19:40 bpf-next 4748a67f7111 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/25 18:21 bpf-next 4748a67f7111 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/24 21:42 net-next 89d8006259b8 05b26a28 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/15 20:17 linux-next cc2b5f627e8c 209f0369 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/02 22:04 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci ff4c5a0de1f2 2b70b115 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/07/16 04:20 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 58717b2a1365 27a8bd60 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm32 BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
2026/06/19 06:47 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 83f1454877cc d7ffd47b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 BUG: using smp_processor_id() in preemptible code in bpf_mem_cache_free_rcu
* Struck through repros no longer work on HEAD.