UBSAN: array-index-out-of-bounds in alg_bind

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    726eb70e Merge tag 'char-misc-5.10-rc1' of git://git.kerne..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1011b678500000
kernel config:  https://syzkaller.appspot.com/x/.config?x=89a0a83d1be17a89
dashboard link: https://syzkaller.appspot.com/bug?extid=92ead4eb8e26a26d465e
compiler:       clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)

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+92ead4eb8e26a26d465e@xxxxxxxxxxxxxxxxxxxxxxxxx

================================================================================
UBSAN: array-index-out-of-bounds in crypto/af_alg.c:166:2
index 91 is out of range for type '__u8 [64]'
CPU: 1 PID: 8236 Comm: syz-executor.0 Not tainted 5.9.0-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+0x1d6/0x29e lib/dump_stack.c:118
 ubsan_epilogue lib/ubsan.c:148 [inline]
 __ubsan_handle_out_of_bounds+0xdb/0x130 lib/ubsan.c:356
 alg_bind+0x738/0x740 crypto/af_alg.c:166
 __sys_bind+0x283/0x360 net/socket.c:1656
 __do_sys_bind net/socket.c:1667 [inline]
 __se_sys_bind net/socket.c:1665 [inline]
 __x64_sys_bind+0x76/0x80 net/socket.c:1665
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45de59
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f547948ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 0000000000000ac0 RCX: 000000000045de59
RDX: 0000000000000074 RSI: 0000000020000940 RDI: 0000000000000003
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffd6121d5bf R14: 00007f547948f9c0 R15: 000000000118bf2c
================================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 8236 Comm: syz-executor.0 Not tainted 5.9.0-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+0x1d6/0x29e lib/dump_stack.c:118
 panic+0x316/0x910 kernel/panic.c:231
 ubsan_epilogue lib/ubsan.c:162 [inline]
 __ubsan_handle_out_of_bounds+0x12b/0x130 lib/ubsan.c:356
 alg_bind+0x738/0x740 crypto/af_alg.c:166
 __sys_bind+0x283/0x360 net/socket.c:1656
 __do_sys_bind net/socket.c:1667 [inline]
 __se_sys_bind net/socket.c:1665 [inline]
 __x64_sys_bind+0x76/0x80 net/socket.c:1665
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45de59
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f547948ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 0000000000000ac0 RCX: 000000000045de59
RDX: 0000000000000074 RSI: 0000000020000940 RDI: 0000000000000003
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffd6121d5bf R14: 00007f547948f9c0 R15: 000000000118bf2c
Kernel Offset: disabled
Rebooting in 86400 seconds..


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