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general protection fault in rds_tcp_skbuf_handler

Status: closed as invalid on 2025/01/15 12:19
Subsystems: rds
[Documentation on labels]
First crash: 36d, last: 36d

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
CPU: 0 UID: 0 PID: 5829 Comm: syz-executor Not tainted 6.13.0-rc2-syzkaller-00333-ga0e3919a2df2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
RIP: 0010:rds_tcp_skbuf_handler+0x67/0x2e0 net/rds/tcp.c:688
Code: 48 c1 ea 03 80 3c 02 00 0f 85 58 02 00 00 4d 8b bf 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7f 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 28 02 00 00 48 89 da 4d 89 f0 4c 89 e9 4d 8b 7f
RSP: 0018:ffffc90003faf5b0 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff888027898c00 RCX: ffffc90003faf620
RDX: 0000000000000005 RSI: ffffffff8a6dfe29 RDI: 0000000000000028
RBP: 0000000000000001 R08: ffffc90003faf710 R09: 0000000000000040
R10: 0000000000000040 R11: 00000000726f7475 R12: ffff8880345da100
R13: ffffc90003faf620 R14: ffffc90003faf710 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f24e88b4440 CR3: 0000000065184000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 proc_sys_call_handler+0x403/0x5d0 fs/proc/proc_sysctl.c:601
 __kernel_write_iter+0x318/0xa80 fs/read_write.c:612
 __kernel_write+0xf6/0x140 fs/read_write.c:632
 do_acct_process+0xcb0/0x14a0 kernel/acct.c:539
 acct_pin_kill+0x2d/0x100 kernel/acct.c:192
 pin_kill+0x194/0x7c0 fs/fs_pin.c:44
 mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81
 cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366
 task_work_run+0x14e/0x250 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xadd/0x2d70 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
 get_signal+0x2576/0x2610 kernel/signal.c:3017
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2073d7bf97
Code: Unable to access opcode bytes at 0x7f2073d7bf6d.
RSP: 002b:00007ffe95e24550 EFLAGS: 00000293 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 00000000000001bd RCX: 00007f2073d7bf97
RDX: 0000000040000000 RSI: 00007ffe95e245ac RDI: 00000000ffffffff
RBP: 00007ffe95e245ac R08: 0000000000000000 R09: 00007f2074ad3000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 000055558c9ef590 R14: 00007ffe95e24600 R15: 0000000000000098
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:rds_tcp_skbuf_handler+0x67/0x2e0 net/rds/tcp.c:688
Code: 48 c1 ea 03 80 3c 02 00 0f 85 58 02 00 00 4d 8b bf 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7f 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 28 02 00 00 48 89 da 4d 89 f0 4c 89 e9 4d 8b 7f
RSP: 0018:ffffc90003faf5b0 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff888027898c00 RCX: ffffc90003faf620
RDX: 0000000000000005 RSI: ffffffff8a6dfe29 RDI: 0000000000000028
RBP: 0000000000000001 R08: ffffc90003faf710 R09: 0000000000000040
R10: 0000000000000040 R11: 00000000726f7475 R12: ffff8880345da100
R13: ffffc90003faf620 R14: ffffc90003faf710 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055860d3a7250 CR3: 000000000db7e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	48 c1 ea 03          	shr    $0x3,%rdx
   4:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   8:	0f 85 58 02 00 00    	jne    0x266
   e:	4d 8b bf 08 09 00 00 	mov    0x908(%r15),%r15
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	49 8d 7f 28          	lea    0x28(%r15),%rdi
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 28 02 00 00    	jne    0x25c
  34:	48 89 da             	mov    %rbx,%rdx
  37:	4d 89 f0             	mov    %r14,%r8
  3a:	4c 89 e9             	mov    %r13,%rcx
  3d:	4d                   	rex.WRB
  3e:	8b                   	.byte 0x8b
  3f:	7f                   	.byte 0x7f

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/15 06:12 upstream a0e3919a2df2 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto general protection fault in rds_tcp_skbuf_handler
* Struck through repros no longer work on HEAD.