syzbot


WARNING in skb_ensure_writable

Status: fixed on 2024/07/09 19:14
Subsystems: bpf net
[Documentation on labels]
Reported-by: syzbot+0c4150bff9fff3bf023c@syzkaller.appspotmail.com
Fix commit: 2bbe3e5a2f4e bpf: Avoid splat in pskb_pull_reason
First crash: 200d, last: 69d
Cause bisection: introduced by (bisect log) :
commit 219eee9c0d16f1b754a8b85275854ab17df0850a
Author: Florian Westphal <fw@strlen.de>
Date: Fri Feb 16 11:36:57 2024 +0000

  net: skbuff: add overflow debug check to pull/push helpers

Crash: WARNING in skb_ensure_writable (log)
Repro: C syz .config
  
Discussions (4)
Title Replies (including bot) Last reply
[Patch net] net: remove the bogus overflow debug check in pskb_may_pull() 10 (10) 2024/06/14 15:30
[syzbot] Monthly net report (May 2024) 0 (1) 2024/05/31 06:48
[syzbot] Monthly bpf report (May 2024) 0 (1) 2024/05/12 18:21
[syzbot] [bpf?] [net?] WARNING in skb_ensure_writable 2 (3) 2024/04/22 14:52
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in skb_ensure_writable C done 496 81d 156d 3/3 fixed on 2024/08/06 01:13
upstream WARNING in skb_ensure_writable (2) bpf net 26 34d 30d 0/28 upstream: reported on 2024/08/17 19:01
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/03/01 17:31 1h15m edumazet@google.com patch net-next OK log

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5066 at include/linux/skbuff.h:2740 pskb_may_pull_reason include/linux/skbuff.h:2740 [inline]
WARNING: CPU: 1 PID: 5066 at include/linux/skbuff.h:2740 pskb_may_pull include/linux/skbuff.h:2756 [inline]
WARNING: CPU: 1 PID: 5066 at include/linux/skbuff.h:2740 skb_ensure_writable+0x2ef/0x440 net/core/skbuff.c:6100
Modules linked in:
CPU: 1 PID: 5066 Comm: syz-executor349 Not tainted 6.8.0-syzkaller-05271-gf99c5f563c17 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:pskb_may_pull_reason include/linux/skbuff.h:2740 [inline]
RIP: 0010:pskb_may_pull include/linux/skbuff.h:2756 [inline]
RIP: 0010:skb_ensure_writable+0x2ef/0x440 net/core/skbuff.c:6100
Code: e8 f6 f2 53 f8 4c 89 ef 31 f6 31 d2 b9 20 08 00 00 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d e9 07 03 fe ff e8 d2 f2 53 f8 90 <0f> 0b 90 e9 3e fd ff ff 44 89 f7 44 89 e6 e8 7e f4 53 f8 45 39 e6
RSP: 0018:ffffc900039a78f0 EFLAGS: 00010293
RAX: ffffffff8940fd9e RBX: ffff88802c6608c0 RCX: ffff88801bbd8000
RDX: 0000000000000000 RSI: 00000000fffffff7 RDI: 0000000000000000
RBP: 00000000fffffff7 R08: ffffffff8940fad7 R09: 1ffffffff1f0d5cd
R10: dffffc0000000000 R11: ffffffffa0001ae4 R12: 00000000fffffff7
R13: ffff88802c6608c0 R14: ffffc90000ace030 R15: dffffc0000000000
FS:  00005555907b7380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000038e49398 CR3: 000000001f4ec000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __bpf_try_make_writable net/core/filter.c:1665 [inline]
 bpf_try_make_writable net/core/filter.c:1671 [inline]
 ____bpf_skb_pull_data net/core/filter.c:1862 [inline]
 bpf_skb_pull_data+0x7c/0x230 net/core/filter.c:1851
 bpf_prog_c054a5fa89446ea8+0x24/0x47
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 bpf_test_run+0x409/0x900 net/bpf/test_run.c:425
 bpf_prog_test_run_skb+0xafa/0x13a0 net/bpf/test_run.c:1058
 bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4240
 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5649
 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f301a4ae669
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffe6cb6d58 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fffe6cb6f28 RCX: 00007f301a4ae669
RDX: 0000000000000050 RSI: 00000000200002c0 RDI: 000000000000000a
RBP: 00007f301a521610 R08: 0000000000000000 R09: 00007fffe6cb6f28
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fffe6cb6f18 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Crashes (2893):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/16 14:36 net f99c5f563c17 0d592ce4 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in skb_ensure_writable
2024/04/16 14:17 net f99c5f563c17 0d592ce4 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in skb_ensure_writable
2024/04/16 13:26 net f99c5f563c17 0d592ce4 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in skb_ensure_writable
2024/04/15 09:56 bpf 443574b03387 c8349e48 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/04/15 09:37 bpf 443574b03387 c8349e48 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/04/15 08:16 bpf 443574b03387 c8349e48 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/05/17 04:07 net-next 1b294a1f3561 c2e07261 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in skb_ensure_writable
2024/05/17 03:48 net-next 1b294a1f3561 c2e07261 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in skb_ensure_writable
2024/05/17 02:55 net-next 1b294a1f3561 c2e07261 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in skb_ensure_writable
2024/05/08 11:20 bpf-next 7e2c7a3f732b 4cf3f9b3 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/05/08 11:01 bpf-next 7e2c7a3f732b 4cf3f9b3 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/05/08 10:20 bpf-next 7e2c7a3f732b 4cf3f9b3 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/02/29 03:43 net-next 4ac828960a60 352ab904 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in skb_ensure_writable
2024/04/15 02:13 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci b5d2afe8745b c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in skb_ensure_writable
2024/06/20 03:43 upstream 2ccbdf43d5e7 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in skb_ensure_writable
2024/06/19 18:32 upstream 2ccbdf43d5e7 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in skb_ensure_writable
2024/06/19 15:10 upstream 2ccbdf43d5e7 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in skb_ensure_writable
2024/06/19 11:48 upstream 2ccbdf43d5e7 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in skb_ensure_writable
2024/06/18 23:39 upstream 2ccbdf43d5e7 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in skb_ensure_writable
2024/06/18 17:54 upstream 2ccbdf43d5e7 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in skb_ensure_writable
2024/04/11 06:12 upstream fe46a7dd189e 56086b24 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in skb_ensure_writable
2024/06/18 15:12 upstream 2ccbdf43d5e7 c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in skb_ensure_writable
2024/06/19 21:55 upstream 92e5605a199e 41b7e219 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in skb_ensure_writable
2024/06/18 13:18 upstream 2ccbdf43d5e7 c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in skb_ensure_writable
2024/06/15 08:43 upstream c286c21ff942 f429ab00 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm32 WARNING in skb_ensure_writable
2024/05/31 04:35 upstream 4a4be1ad3a6e 34889ee3 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-compat WARNING in skb_ensure_writable
2024/05/30 18:50 upstream 4a4be1ad3a6e 34889ee3 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 WARNING in skb_ensure_writable
2024/06/24 07:53 bpf 36534d3c5453 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/24 01:04 bpf 36534d3c5453 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/24 00:52 bpf 36534d3c5453 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/23 19:53 bpf 36534d3c5453 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/21 23:51 bpf 36534d3c5453 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/21 14:02 bpf 36534d3c5453 dac2aa43 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/20 23:46 bpf 36534d3c5453 dac2aa43 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/20 09:01 net be27b8965297 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in skb_ensure_writable
2024/06/20 03:42 bpf 36534d3c5453 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/19 10:32 net be27b8965297 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in skb_ensure_writable
2024/06/19 04:35 bpf 36534d3c5453 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/06/19 01:04 bpf 36534d3c5453 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in skb_ensure_writable
2024/07/09 00:43 bpf-next a5912c37faf7 cde64f7d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/07 17:45 bpf-next fd8db07705c5 bc4ebbb5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/07 16:27 bpf-next fd8db07705c5 bc4ebbb5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/07 12:52 bpf-next fd8db07705c5 bc4ebbb5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/07 03:55 bpf-next fd8db07705c5 bc4ebbb5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/06 00:23 bpf-next fd8db07705c5 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/05 03:26 bpf-next fd8db07705c5 dc6bbff0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/04 21:00 bpf-next fd8db07705c5 dc6bbff0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/04 12:05 bpf-next fd8db07705c5 409d975c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/04 11:54 bpf-next fd8db07705c5 409d975c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/03 23:44 bpf-next fd8db07705c5 409d975c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/03 13:53 bpf-next fd8db07705c5 409d975c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/03 08:03 bpf-next fd8db07705c5 1ecfa2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/01 23:33 bpf-next 5b747c23f17d b294e901 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/01 15:35 bpf-next a12978712d90 b294e901 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/07/01 00:51 bpf-next a12978712d90 757f06b1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/30 03:08 bpf-next a12978712d90 757f06b1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/29 08:15 bpf-next a12978712d90 757f06b1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/28 08:56 bpf-next a12978712d90 b62c7d46 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/27 22:11 bpf-next a12978712d90 b62c7d46 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/27 00:27 bpf-next aa293983d202 880c1ca1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/26 08:51 bpf-next d65f3767de20 dec8bc94 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/25 23:46 bpf-next c73a9683cb21 da0bd5ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/23 09:11 bpf-next 1ae7a19e3763 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/22 17:32 bpf-next 1ae7a19e3763 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/21 21:36 bpf-next 1ae7a19e3763 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/19 23:02 bpf-next f6afdaf72af7 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/19 01:15 bpf-next f6afdaf72af7 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in skb_ensure_writable
2024/06/18 19:10 net-next 3ec8d7572a69 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in skb_ensure_writable
2024/06/12 12:40 linux-next a957267fa7e9 4d75f4f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in skb_ensure_writable
2024/06/24 05:33 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci ac2193b4b460 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in skb_ensure_writable
2024/06/23 21:51 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci ac2193b4b460 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in skb_ensure_writable
2024/06/23 19:50 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci ac2193b4b460 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in skb_ensure_writable
2024/06/19 13:03 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci ac2193b4b460 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in skb_ensure_writable
* Struck through repros no longer work on HEAD.