general protection fault in copy_process

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=122bb4ecb00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=0c8fa9184c8f7eb1e7e7
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0c8fa9...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 27285 Comm: syz-executor.3 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__rb_insert lib/rbtree.c:131 [inline]
RIP: 0010:__rb_insert_augmented+0x96/0x920 lib/rbtree.c:495
Code: ea 48 c1 ea 03 42 80 3c 2a 00 0f 85 81 05 00 00 4c 8b 65 00 41 f6 c4 01 0f 85 6e 03 00 00 4d 8d 44 24 08 4c 89 c2 48 c1 ea 03 <42> 80 3c 2a 00 0f 85 71 05 00 00 4d 8b 74 24 08 49 39 ee 0f 84 76
RSP: 0018:ffff888225c47b88 EFLAGS: 00010202
RAX: ffff8880b540a320 RBX: ffff88809ca34bb0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffff88809ca34bc0
RBP: ffff88800012f3b0 R08: 0000000000000008 R09: 00000000000001ff
R10: 0000000000000006 R11: 00000000d2cc1d79 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888079fc08d8 R15: ffffffff81897a50
FS: 00007f073ef9a700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7a9ae3a010 CR3: 00000000792d0000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
dup_mmap kernel/fork.c:521 [inline]
dup_mm kernel/fork.c:1285 [inline]
copy_mm kernel/fork.c:1341 [inline]
copy_process.part.0+0x3121/0x8260 kernel/fork.c:1913
copy_process kernel/fork.c:1710 [inline]
_do_fork+0x22f/0xf30 kernel/fork.c:2219
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f0741a24ae9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f073ef9a188 EFLAGS: 00000246 ORIG_RAX: 0000000000000039
RAX: ffffffffffffffda RBX: 00007f0741b37f60 RCX: 00007f0741a24ae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f0741a7ef25 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc448ab06f R14: 00007f073ef9a300 R15: 0000000000022000
Modules linked in:
---[ end trace 8c99c4d590f35d0e ]---
RIP: 0010:__rb_insert lib/rbtree.c:131 [inline]
RIP: 0010:__rb_insert_augmented+0x96/0x920 lib/rbtree.c:495
Code: ea 48 c1 ea 03 42 80 3c 2a 00 0f 85 81 05 00 00 4c 8b 65 00 41 f6 c4 01 0f 85 6e 03 00 00 4d 8d 44 24 08 4c 89 c2 48 c1 ea 03 <42> 80 3c 2a 00 0f 85 71 05 00 00 4d 8b 74 24 08 49 39 ee 0f 84 76
RSP: 0018:ffff888225c47b88 EFLAGS: 00010202
RAX: ffff8880b540a320 RBX: ffff88809ca34bb0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffff88809ca34bc0
RBP: ffff88800012f3b0 R08: 0000000000000008 R09: 00000000000001ff
R10: 0000000000000006 R11: 00000000d2cc1d79 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888079fc08d8 R15: ffffffff81897a50
FS: 00007f073ef9a700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555556aaa3bc CR3: 00000000792d0000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 48 c1 ea 03 shr $0x3,%rdx
4: 42 80 3c 2a 00 cmpb $0x0,(%rdx,%r13,1)
9: 0f 85 81 05 00 00 jne 0x590
f: 4c 8b 65 00 mov 0x0(%rbp),%r12
13: 41 f6 c4 01 test $0x1,%r12b
17: 0f 85 6e 03 00 00 jne 0x38b
1d: 4d 8d 44 24 08 lea 0x8(%r12),%r8
22: 4c 89 c2 mov %r8,%rdx
25: 48 c1 ea 03 shr $0x3,%rdx
* 29: 42 80 3c 2a 00 cmpb $0x0,(%rdx,%r13,1) <-- trapping instruction
2e: 0f 85 71 05 00 00 jne 0x5a5
34: 4d 8b 74 24 08 mov 0x8(%r12),%r14
39: 49 39 ee cmp %rbp,%r14
3c: 0f .byte 0xf
3d: 84 .byte 0x84
3e: 76 .byte 0x76


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.