syzbot


WARNING in skb_ensure_writable

Status: fixed on 2024/08/06 01:13
Reported-by: syzbot+6a277a9044a785b43d58@syzkaller.appspotmail.com
Fix commit: dacc15e9cb24 bpf: Avoid splat in pskb_pull_reason
First crash: 234d, last: 159d
Fix bisection: fixed by (bisect log) :
commit dacc15e9cb248d19e5fc63c54bef0b9b55007761
Author: Florian Westphal <fw@strlen.de>
Date: Fri Jun 14 10:17:33 2024 +0000

  bpf: Avoid splat in pskb_pull_reason

  
Bug presence (1)
Date Name Commit Repro Result
2024/07/30 upstream (ToT) 94ede2a3e913 C Didn't crash
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in skb_ensure_writable bpf net C done 2893 147d 225d 26/28 fixed on 2024/07/09 19:14
upstream WARNING in skb_ensure_writable (2) bpf net 26 111d 107d 0/28 auto-obsoleted due to no activity on 2024/10/23 00:05

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3547 at include/linux/skbuff.h:2641 skb_ensure_writable+0x2e6/0x430 net/core/skbuff.c:5768
Modules linked in:
CPU: 0 PID: 3547 Comm: syz-executor170 Not tainted 6.1.86-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:pskb_may_pull include/linux/skbuff.h:2641 [inline]
RIP: 0010:skb_ensure_writable+0x2e6/0x430 net/core/skbuff.c:5768
Code: c3 e8 4e 57 0e f9 4c 89 ef 31 f6 31 d2 b9 20 0a 00 00 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d e9 9f 0f fe ff e8 2a 57 0e f9 <0f> 0b e9 44 fd ff ff 44 89 f7 44 89 e6 e8 78 58 0e f9 45 39 e6 0f
RSP: 0018:ffffc9000390f910 EFLAGS: 00010293
RAX: ffffffff887c3826 RBX: ffff888072284640 RCX: ffff8880273c1dc0
RDX: 0000000000000000 RSI: 00000000fffffff7 RDI: 0000000000000000
RBP: 00000000fffffff7 R08: ffffffff887c3563 R09: fffffbfff1ce6ede
R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000fffffff7
R13: ffff888072284640 R14: ffffc90000b1e020 R15: dffffc0000000000
FS:  0000555555b2a380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002c80 CR3: 0000000072280000 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:1658 [inline]
 bpf_try_make_writable net/core/filter.c:1664 [inline]
 ____bpf_skb_pull_data net/core/filter.c:1844 [inline]
 bpf_skb_pull_data+0x78/0x220 net/core/filter.c:1833
 bpf_prog_c054a5fa89446ea8+0x1c/0x3f
 bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 bpf_test_run+0x40f/0x8b0 net/bpf/test_run.c:402
 bpf_prog_test_run_skb+0xaf1/0x13a0 net/bpf/test_run.c:1180
 bpf_prog_test_run+0x32f/0x3a0 kernel/bpf/syscall.c:3670
 __sys_bpf+0x3eb/0x6c0 kernel/bpf/syscall.c:5023
 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5107 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd366ea3669
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:00007fffda169d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fffda169f68 RCX: 00007fd366ea3669
RDX: 0000000000000050 RSI: 00000000200002c0 RDI: 000000000000000a
RBP: 00007fd366f16610 R08: 0000000000000000 R09: 00007fffda169f68
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fffda169f58 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Crashes (496):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/13 20:42 linux-6.1.y cd5d98c0556c c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/04/13 20:15 linux-6.1.y cd5d98c0556c c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/04/13 19:23 linux-6.1.y cd5d98c0556c c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/04/13 14:44 linux-6.1.y cd5d98c0556c c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/04/13 18:58 linux-6.1.y cd5d98c0556c c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/27 05:49 linux-6.1.y eb44d83053d6 c6d33a01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/24 09:58 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/24 08:34 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/24 07:19 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/24 04:43 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/24 02:04 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/23 23:35 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/23 20:13 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/23 02:00 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/22 02:04 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/21 01:24 linux-6.1.y eb44d83053d6 dac2aa43 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/20 06:08 linux-6.1.y eb44d83053d6 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/19 15:43 linux-6.1.y eb44d83053d6 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/19 11:40 linux-6.1.y eb44d83053d6 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/19 05:44 linux-6.1.y eb44d83053d6 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/18 20:10 linux-6.1.y eb44d83053d6 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/18 18:00 linux-6.1.y eb44d83053d6 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/13 10:08 linux-6.1.y ae9f2a70d69e 2aa5052f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/13 04:34 linux-6.1.y ae9f2a70d69e 2aa5052f .config console log report info ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/12 07:24 linux-6.1.y 88690811da69 4d75f4f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/11 22:00 linux-6.1.y 88690811da69 4d75f4f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/11 20:16 linux-6.1.y 88690811da69 4d75f4f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/11 14:22 linux-6.1.y 88690811da69 b7d9eb04 .config console log report info ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/11 14:22 linux-6.1.y 88690811da69 b7d9eb04 .config console log report info ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/11 01:19 linux-6.1.y 88690811da69 048c640a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/10 02:43 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/09 20:53 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/08 12:23 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in skb_ensure_writable
2024/06/08 09:51 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/08 07:29 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/04/13 13:04 linux-6.1.y cd5d98c0556c c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in skb_ensure_writable
2024/06/27 01:06 linux-6.1.y eb44d83053d6 c6d33a01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/26 09:49 linux-6.1.y eb44d83053d6 dec8bc94 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/24 05:37 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/24 01:03 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/23 22:00 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/23 19:57 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/20 03:48 linux-6.1.y eb44d83053d6 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/19 11:21 linux-6.1.y eb44d83053d6 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/18 23:05 linux-6.1.y eb44d83053d6 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/13 09:34 linux-6.1.y ae9f2a70d69e 2aa5052f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/12 17:37 linux-6.1.y ae9f2a70d69e f815599d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/10 23:02 linux-6.1.y 88690811da69 048c640a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/10 00:16 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/08 17:46 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
2024/06/08 17:44 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in skb_ensure_writable
* Struck through repros no longer work on HEAD.