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general protection fault in skb_clone (6)

Status: closed as invalid on 2026/03/30 17:42
Subsystems: hams
[Documentation on labels]
First crash: 40d, last: 40d
Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 general protection fault in skb_clone 2 C 1 1133d 1267d 0/1 upstream: reported C repro on 2022/10/17 02:33
upstream general protection fault in skb_clone 2 syz 3 3154d 3154d 3/29 fixed on 2017/10/24 19:00
upstream BUG: unable to handle kernel paging request in skb_clone net 8 2 1696d 1741d 0/29 closed as invalid on 2021/10/04 21:36
upstream general protection fault in skb_clone (3) net 2 44 2139d 2141d 15/29 fixed on 2020/07/17 17:58
linux-4.19 general protection fault in skb_clone 2 C error 2 1266d 1576d 0/1 upstream: reported C repro on 2021/12/12 07:38
upstream general protection fault in skb_clone (4) net 10 C unreliable 41 1279d 1576d 0/29 closed as invalid on 2022/10/12 18:15
upstream general protection fault in skb_clone (2) hams 2 1 2322d 2320d 0/29 auto-closed as invalid on 2020/03/25 12:28
upstream general protection fault in skb_clone (5) net 10 C done 7 1252d 1270d 22/29 fixed on 2023/02/24 13:50
upstream KMSAN: uninit-value in skb_clone batman 7 C 3 133d 131d 29/29 fixed on 2026/01/21 09:45

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000f: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000078-0x000000000000007f]
CPU: 0 UID: 0 PID: 16 Comm: ktimers/0 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:skb_clone+0xd7/0x3a0 net/core/skbuff.c:2111
Code: 03 42 80 3c 20 00 74 08 4c 89 f7 e8 93 1c 3d f9 49 83 3e 00 0f 85 a0 01 00 00 e8 64 13 d7 f8 48 8d 6b 7e 49 89 ee 49 c1 ee 03 <43> 0f b6 04 26 84 c0 0f 85 d1 01 00 00 44 0f b6 7d 00 41 83 e7 0c
RSP: 0018:ffffc90000157668 EFLAGS: 00010207
RAX: ffffffff88ed3f51 RBX: 0000000000000000 RCX: ffff88801caa8000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000100
RBP: 000000000000007e R08: ffffffff8f6a25b7 R09: 1ffffffff1ed44b6
R10: dffffc0000000000 R11: fffffbfff1ed44b7 R12: dffffc0000000000
R13: 0000000000000820 R14: 000000000000000f R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888126343000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d312ff8 CR3: 000000002acfe000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 nr_kick+0x223/0x690 net/netrom/nr_out.c:158
 nr_process_rx_frame+0x138f/0x1720 net/netrom/nr_in.c:298
 nr_rx_frame+0x5d1/0x1b80 net/netrom/af_netrom.c:938
 nr_loopback_timer+0x6e/0x1a0 net/netrom/nr_loopback.c:59
 call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x6a3/0x9f0 kernel/time/timer.c:2385
 run_timer_base kernel/time/timer.c:2394 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
 handle_softirqs+0x1de/0x6f0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0x69/0x100 kernel/softirq.c:1138
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:skb_clone+0xd7/0x3a0 net/core/skbuff.c:2111
Code: 03 42 80 3c 20 00 74 08 4c 89 f7 e8 93 1c 3d f9 49 83 3e 00 0f 85 a0 01 00 00 e8 64 13 d7 f8 48 8d 6b 7e 49 89 ee 49 c1 ee 03 <43> 0f b6 04 26 84 c0 0f 85 d1 01 00 00 44 0f b6 7d 00 41 83 e7 0c
RSP: 0018:ffffc90000157668 EFLAGS: 00010207
RAX: ffffffff88ed3f51 RBX: 0000000000000000 RCX: ffff88801caa8000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000100
RBP: 000000000000007e R08: ffffffff8f6a25b7 R09: 1ffffffff1ed44b6
R10: dffffc0000000000 R11: fffffbfff1ed44b7 R12: dffffc0000000000
R13: 0000000000000820 R14: 000000000000000f R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888126343000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d312ff8 CR3: 000000002acfe000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	03 42 80             	add    -0x80(%rdx),%eax
   3:	3c 20                	cmp    $0x20,%al
   5:	00 74 08 4c          	add    %dh,0x4c(%rax,%rcx,1)
   9:	89 f7                	mov    %esi,%edi
   b:	e8 93 1c 3d f9       	call   0xf93d1ca3
  10:	49 83 3e 00          	cmpq   $0x0,(%r14)
  14:	0f 85 a0 01 00 00    	jne    0x1ba
  1a:	e8 64 13 d7 f8       	call   0xf8d71383
  1f:	48 8d 6b 7e          	lea    0x7e(%rbx),%rbp
  23:	49 89 ee             	mov    %rbp,%r14
  26:	49 c1 ee 03          	shr    $0x3,%r14
* 2a:	43 0f b6 04 26       	movzbl (%r14,%r12,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 d1 01 00 00    	jne    0x208
  37:	44 0f b6 7d 00       	movzbl 0x0(%rbp),%r15d
  3c:	41 83 e7 0c          	and    $0xc,%r15d

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/25 07:13 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root general protection fault in skb_clone
* Struck through repros no longer work on HEAD.