syzbot


general protection fault in collect_signal

Status: auto-obsoleted due to no activity on 2023/04/15 00:36
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+2efa796c1de7d56946c7@syzkaller.appspotmail.com
First crash: 429d, last: 429d

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 0 PID: 5070 Comm: syz-fuzzer Not tainted 6.2.0-rc7-next-20230208-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
RIP: 0010:collect_signal+0x86/0x630 kernel/signal.c:578
Code: 48 89 d8 48 c1 e8 03 42 80 3c 20 00 0f 85 af 04 00 00 48 8b 1b 49 39 de 74 43 e8 65 c7 34 00 48 8d 7b 18 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 74 08 3c 03 0f 8e 93 04 00 00 44 8b 7b 18 89
RSP: 0018:ffffc90003acfc48 EFLAGS: 00010006
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88801e618000 RSI: ffffffff814fa67b RDI: 0000000000000018
RBP: 0000000000000017 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000000017 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88801e618890 R15: 0000000000000000
FS:  000000c000050490(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efe726d56be CR3: 00000000283b6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __dequeue_signal kernel/signal.c:619 [inline]
 dequeue_signal+0x22e/0x650 kernel/signal.c:639
 get_signal+0x57e/0x25b0 kernel/signal.c:2739
 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
 exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
 exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
 irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0033:0x500da4
Code: 00 00 eb 0c 48 8d ba e0 10 00 00 e8 96 4a f6 ff 48 8b 6c 24 70 48 83 c4 78 c3 49 39 c8 0f 8d a1 00 00 00 48 8b b0 98 10 00 00 <4c> 8b 90 88 10 00 00 48 39 ce 0f 82 dc 01 00 00 49 39 c8 0f 87 cb
RSP: 002b:000000c007d4ed90 EFLAGS: 00000293
RAX: 000000c003b88c00 RBX: 0000000000000020 RCX: 0000000000001253
RDX: 0000000000001151 RSI: 0000000000008000 RDI: 000000c006bc9170
RBP: 000000c007d4ee00 R08: 0000000000001190 R09: 0000000000001150
R10: 000000c006bc8000 R11: 0000000000001253 R12: 0000000000001150
R13: 0000000000001170 R14: 000000c0000001a0 R15: 0000000000000010
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:collect_signal+0x86/0x630 kernel/signal.c:578
Code: 48 89 d8 48 c1 e8 03 42 80 3c 20 00 0f 85 af 04 00 00 48 8b 1b 49 39 de 74 43 e8 65 c7 34 00 48 8d 7b 18 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 74 08 3c 03 0f 8e 93 04 00 00 44 8b 7b 18 89
RSP: 0018:ffffc90003acfc48 EFLAGS: 00010006
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88801e618000 RSI: ffffffff814fa67b RDI: 0000000000000018
RBP: 0000000000000017 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000000017 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88801e618890 R15: 0000000000000000
FS:  000000c000050490(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efe726d56be CR3: 00000000283b6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	48 89 d8             	mov    %rbx,%rax
   3:	48 c1 e8 03          	shr    $0x3,%rax
   7:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
   c:	0f 85 af 04 00 00    	jne    0x4c1
  12:	48 8b 1b             	mov    (%rbx),%rbx
  15:	49 39 de             	cmp    %rbx,%r14
  18:	74 43                	je     0x5d
  1a:	e8 65 c7 34 00       	callq  0x34c784
  1f:	48 8d 7b 18          	lea    0x18(%rbx),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	74 08                	je     0x3b
  33:	3c 03                	cmp    $0x3,%al
  35:	0f 8e 93 04 00 00    	jle    0x4ce
  3b:	44 8b 7b 18          	mov    0x18(%rbx),%r15d
  3f:	89                   	.byte 0x89

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/14 00:35 linux-next 38d2b86a665b 93ae7e0a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in collect_signal
* Struck through repros no longer work on HEAD.