WARNING in af_alg_make_sg

From: syzbot
Date: Wed Apr 08 2020 - 03:48:16 EST


Hello,

syzbot found the following crash on:

HEAD commit: 763dede1 Merge tag 'for-linus-5.7-rc1' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12b919c7e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=12205d036cec317f
dashboard link: https://syzkaller.appspot.com/bug?extid=3be1a33f04dc782e9fd5
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=142f3b8fe00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=159bd23fe00000

The bug was bisected to:

commit 4426e945df588f2878affddf88a51259200f7e29
Author: Peter Xu <peterx@xxxxxxxxxx>
Date: Thu Apr 2 04:08:49 2020 +0000

mm/gup: allow VM_FAULT_RETRY for multiple times

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1408ea9fe00000
final crash: https://syzkaller.appspot.com/x/report.txt?x=1608ea9fe00000
console output: https://syzkaller.appspot.com/x/log.txt?x=1208ea9fe00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+3be1a33f04dc782e9fd5@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 4426e945df58 ("mm/gup: allow VM_FAULT_RETRY for multiple times")

------------[ cut here ]------------
WARNING: CPU: 1 PID: 7094 at crypto/af_alg.c:404 af_alg_make_sg+0x399/0x400 crypto/af_alg.c:404
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 7094 Comm: syz-executor037 Not tainted 5.6.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x188/0x20d lib/dump_stack.c:118
panic+0x2e3/0x75c kernel/panic.c:221
__warn.cold+0x2f/0x35 kernel/panic.c:582
report_bug+0x27b/0x2f0 lib/bug.c:195
fixup_bug arch/x86/kernel/traps.c:175 [inline]
fixup_bug arch/x86/kernel/traps.c:170 [inline]
do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:af_alg_make_sg+0x399/0x400 crypto/af_alg.c:404
Code: 5c 24 2b 31 ff 89 de e8 c5 b9 f8 fd 84 db 74 0e e8 8c b8 f8 fd 48 8b 04 24 48 89 44 24 70 e8 7e b8 f8 fd 0f 0b e8 77 b8 f8 fd <0f> 0b c7 44 24 4c ea ff ff ff e9 4b ff ff ff 48 89 df e8 40 6e 36
RSP: 0018:ffffc900018779a0 EFLAGS: 00010293
RAX: ffff8880a16b65c0 RBX: ffff8880a4141220 RCX: ffffffff837a763d
RDX: 0000000000000000 RSI: ffffffff837a78f9 RDI: 0000000000000005
RBP: 000000001fef2254 R08: ffff8880a16b65c0 R09: ffffed10142d6cb9
R10: ffff8880a16b65c7 R11: ffffed10142d6cb8 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
hash_sendmsg+0x45c/0xad0 crypto/algif_hash.c:94
sock_sendmsg_nosec net/socket.c:652 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:672
____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362
___sys_sendmsg+0x100/0x170 net/socket.c:2416
__sys_sendmsg+0xec/0x1b0 net/socket.c:2449
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x446999
Code: e8 0c e8 ff ff 48 83 c4 18 c3 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 0f 83 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1427fb4d98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 0000000000446999
RDX: 0000000000000000 RSI: 00000000200002c0 RDI: 0000000000000005
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000068736168
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
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