[syzbot] [crypto?] KASAN: wild-memory-access Read in __sha512_update

[syzbot <syzbot+e37eedd918576774ec80@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    4ac65880ebca Add linux-next specific files for 20250904
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11136312580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1220fefb3f11f346
dashboard link: https://syzkaller.appspot.com/bug?extid=e37eedd918576774ec80
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15136312580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16e23e62580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/17aafe2d8f53/disk-4ac65880.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/09caead80fb0/vmlinux-4ac65880.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b33c041f8dc2/bzImage-4ac65880.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e37eedd918576774ec80@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: wild-memory-access in __sha512_update+0x10d/0x1d0 lib/crypto/sha512.c:175
Read of size 2 at addr 0005088000000000 by task syz.0.17/6022

CPU: 0 UID: 0 PID: 6022 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:200
 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
 __sha512_update+0x10d/0x1d0 lib/crypto/sha512.c:175
 sha512_update include/crypto/sha2.h:734 [inline]
 crypto_sha512_update+0x27/0x40 crypto/sha512.c:151
 crypto_shash_update include/crypto/hash.h:1006 [inline]
 shash_ahash_update+0x213/0x2f0 crypto/ahash.c:178
 hash_sendmsg+0x96b/0x11d0 crypto/algif_hash.c:149
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 ____sys_sendmsg+0x52d/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmmsg+0x227/0x430 net/socket.c:2757
 __do_sys_sendmmsg net/socket.c:2784 [inline]
 __se_sys_sendmmsg net/socket.c:2781 [inline]
 __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2781
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9e1df8ebe9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd2b583528 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f9e1e1c5fa0 RCX: 00007f9e1df8ebe9
RDX: 0000000000000001 RSI: 0000200000000640 RDI: 0000000000000004
RBP: 00007f9e1e011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9e1e1c5fa0 R14: 00007f9e1e1c5fa0 R15: 0000000000000004
 </TASK>
==================================================================


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