[syzbot] [crypto?] general protection fault in xxh64_update

syzbot
2025-09-08T11:26:28Z

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=12951312580000
kernel config: https://syzkaller.appspot.com/x/.config?x=fbc16d9faf3a88a4
dashboard link: https://syzkaller.appspot.com/bug?extid=14c6a89d5f47cd26ea7a
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=16951312580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10b8e962580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/36645a51612c/disk-4ac65880.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bba80d634bef/vmlinux-4ac65880.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e58dd70dfd0f/bzImage-4ac65880.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+14c6a89d5f47cd26ea7a@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xe0009d1000000000: 0000 [#1] SMP KASAN PTI
KASAN: maybe wild-memory-access in range [0x0005088000000000-0x0005088000000007]
CPU: 0 UID: 0 PID: 6069 Comm: syz.0.32 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:get_unaligned_le64 include/linux/unaligned.h:28 [inline]
RIP: 0010:xxh64_update+0x55b/0xcf0 lib/xxhash.c:312
Code: 00 00 00 fc ff df 48 8b 44 24 30 48 83 c0 e0 48 89 44 24 18 48 89 5c 24 68 48 8b 1b 45 31 ff 4e 8d 0c 3e 4c 89 c8 48 c1 e8 03 <0f> b6 04 10 84 c0 0f 85 4a 01 00 00 4a 8d 3c 3e 48 83 c7 07 48 89
RSP: 0018:ffffc900039c7778 EFLAGS: 00010206
RAX: 0000a11000000000 RBX: 7a8f95a9137c12d5 RCX: ffff88802af8bc00
RDX: dffffc0000000000 RSI: 0005088000000000 RDI: 0000000000000000
RBP: 8c2c5b2336b29570 R08: c2b2ae3d27d4eb4f R09: 0005088000000000
R10: 0000000000000000 R11: ffffffff849f4de0 R12: bcfbe54b88bf1c85
R13: ffff88807c933360 R14: 128d621f73d40218 R15: 0000000000000000
FS: 00007fa7a7e826c0(0000) GS:ffff8881259fa000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa7a7e60f98 CR3: 0000000075c6c000 CR4: 00000000003526f0
Call Trace:
<TASK>
xxhash64_update+0x27/0x40 crypto/xxhash_generic.c:46
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+0x505/0x830 net/socket.c:2614
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
__sys_sendmsg net/socket.c:2700 [inline]
__do_sys_sendmsg net/socket.c:2705 [inline]
__se_sys_sendmsg net/socket.c:2703 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
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: 0033:0x7fa7a6f8ebe9
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:00007fa7a7e82038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa7a71c5fa0 RCX: 00007fa7a6f8ebe9
RDX: 0000000000000000 RSI: 0000200000001080 RDI: 0000000000000004
RBP: 00007fa7a7011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa7a71c6038 R14: 00007fa7a71c5fa0 R15: 00007ffc0c907ff8
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:get_unaligned_le64 include/linux/unaligned.h:28 [inline]
RIP: 0010:xxh64_update+0x55b/0xcf0 lib/xxhash.c:312
Code: 00 00 00 fc ff df 48 8b 44 24 30 48 83 c0 e0 48 89 44 24 18 48 89 5c 24 68 48 8b 1b 45 31 ff 4e 8d 0c 3e 4c 89 c8 48 c1 e8 03 <0f> b6 04 10 84 c0 0f 85 4a 01 00 00 4a 8d 3c 3e 48 83 c7 07 48 89
RSP: 0018:ffffc900039c7778 EFLAGS: 00010206
RAX: 0000a11000000000 RBX: 7a8f95a9137c12d5 RCX: ffff88802af8bc00
RDX: dffffc0000000000 RSI: 0005088000000000 RDI: 0000000000000000
RBP: 8c2c5b2336b29570 R08: c2b2ae3d27d4eb4f R09: 0005088000000000
R10: 0000000000000000 R11: ffffffff849f4de0 R12: bcfbe54b88bf1c85
R13: ffff88807c933360 R14: 128d621f73d40218 R15: 0000000000000000
FS: 00007fa7a7e826c0(0000) GS:ffff8881259fa000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa7a7e60f98 CR3: 0000000075c6c000 CR4: 00000000003526f0
----------------
Code disassembly (best guess), 5 bytes skipped:
0: df 48 8b fisttps -0x75(%rax)
3: 44 24 30 rex.R and $0x30,%al
6: 48 83 c0 e0 add $0xffffffffffffffe0,%rax
a: 48 89 44 24 18 mov %rax,0x18(%rsp)
f: 48 89 5c 24 68 mov %rbx,0x68(%rsp)
14: 48 8b 1b mov (%rbx),%rbx
17: 45 31 ff xor %r15d,%r15d
1a: 4e 8d 0c 3e lea (%rsi,%r15,1),%r9
1e: 4c 89 c8 mov %r9,%rax
21: 48 c1 e8 03 shr $0x3,%rax
* 25: 0f b6 04 10 movzbl (%rax,%rdx,1),%eax <-- trapping instruction
29: 84 c0 test %al,%al
2b: 0f 85 4a 01 00 00 jne 0x17b
31: 4a 8d 3c 3e lea (%rsi,%r15,1),%rdi
35: 48 83 c7 07 add $0x7,%rdi
39: 48 rex.W
3a: 89 .byte 0x89

---
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