syzbot


KMSAN: uninit-value in poly1305_blocks

Status: upstream: reported C repro on 2025/10/20 21:07
Subsystems: crypto
[Documentation on labels]
Reported-by: syzbot+01fcd39a0d90cdb0e3df@syzkaller.appspotmail.com
First crash: 1d16h, last: 1d00h
Discussions (6)
Title Replies (including bot) Last reply
[PATCH] lib/crypto: poly1305: Restore dependency of arch code on !KMSAN 1 (1) 2025/10/22 03:34
[PATCH] lib/crypto: poly1305: fix uninit-value in poly1305_blocks 5 (5) 2025/10/21 15:14
[PATCH] syz test 1 (2) 2025/10/21 09:21
Re: [PATCH] [patch] syz test 1 (1) 2025/10/21 05:25
[PATCH] [patch] syz test 3 (5) 2025/10/21 04:46
[syzbot] [crypto?] KMSAN: uninit-value in poly1305_blocks 0 (1) 2025/10/20 21:07
Last patch testing requests (3)
Created Duration User Patch Repo Result
2025/10/21 08:35 29m xiaopei01@kylinos.cn patch upstream OK log
2025/10/21 03:09 58m xiaopei01@kylinos.cn patch upstream OK log
2025/10/21 01:54 38m xiaopei01@kylinos.cn patch upstream report log

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in poly1305_blocks+0x1a9/0x5f0 lib/crypto/x86/poly1305.h:110
 poly1305_blocks+0x1a9/0x5f0 lib/crypto/x86/poly1305.h:110
 poly1305_update+0x169/0x400 lib/crypto/poly1305.c:50
 poly_hash+0x9f3/0x1a00 crypto/chacha20poly1305.c:168
 poly_genkey+0x3b6/0x450 crypto/chacha20poly1305.c:233
 chacha_encrypt crypto/chacha20poly1305.c:269 [inline]
 chachapoly_encrypt+0x48a/0x5c0 crypto/chacha20poly1305.c:284
 crypto_aead_encrypt+0xe2/0x160 crypto/aead.c:91
 tls_do_encryption net/tls/tls_sw.c:582 [inline]
 tls_push_record+0x38c7/0x5810 net/tls/tls_sw.c:819
 bpf_exec_tx_verdict+0x1a0c/0x26a0 net/tls/tls_sw.c:859
 tls_sw_sendmsg_locked net/tls/tls_sw.c:1138 [inline]
 tls_sw_sendmsg+0x3401/0x4560 net/tls/tls_sw.c:1281
 inet6_sendmsg+0x26c/0x2a0 net/ipv6/af_inet6.c:659
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x145/0x3d0 net/socket.c:742
 sock_write_iter+0x3a6/0x420 net/socket.c:1195
 do_iter_readv_writev+0x9e1/0xc20 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable desc created at:
 poly_hash+0x11d/0x1a00 crypto/chacha20poly1305.c:135
 poly_genkey+0x3b6/0x450 crypto/chacha20poly1305.c:233

CPU: 1 UID: 0 PID: 6030 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
=====================================================

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/20 17:31 upstream 211ddde0823f 1c8c8cd8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in poly1305_blocks
2025/10/20 16:07 upstream 211ddde0823f 1c8c8cd8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in poly1305_blocks
2025/10/20 13:51 upstream 211ddde0823f 1c8c8cd8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in poly1305_blocks
2025/10/20 11:44 upstream 211ddde0823f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in poly1305_blocks
2025/10/20 11:44 upstream 211ddde0823f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in poly1305_blocks
2025/10/21 03:27 upstream 211ddde0823f 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in poly1305_blocks
2025/10/21 03:19 upstream 211ddde0823f 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in poly1305_blocks
2025/10/21 03:19 upstream 211ddde0823f 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in poly1305_blocks
2025/10/21 03:16 upstream 211ddde0823f 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in poly1305_blocks
2025/10/21 03:15 upstream 211ddde0823f 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in poly1305_blocks
* Struck through repros no longer work on HEAD.