syzbot


KMSAN: uninit-value in io_issue_sqe

Status: fixed on 2024/06/11 03:41
Subsystems: io-uring
[Documentation on labels]
Reported-by: syzbot+b1647099e82b3b349fbf@syzkaller.appspotmail.com
Fix commit: 18414a4a2eab io_uring/net: assign kmsg inq/flags before buffer selection
First crash: 28d, last: 14d
Duplicate bugs (1)
duplicates (1):
Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
KMSAN: uninit-value in io_req_cqe_overflow (2) io-uring C 48 14d 37d 0/27 closed as dup on 2024/05/30 20:10
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] [io-uring?] KMSAN: uninit-value in io_issue_sqe 1 (2) 2024/05/30 20:07
[PATCH] io_uring/net: assign kmsg inq/flags before buffer selection 1 (1) 2024/05/30 20:05
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in io_issue_sqe io-uring fs C done unreliable 502 669d 1026d 0/27 auto-obsoleted due to no activity on 2023/04/19 14:13

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in io_req_cqe_overflow io_uring/io_uring.c:810 [inline]
BUG: KMSAN: uninit-value in io_req_complete_post io_uring/io_uring.c:937 [inline]
BUG: KMSAN: uninit-value in io_issue_sqe+0x1f1b/0x22c0 io_uring/io_uring.c:1763
 io_req_cqe_overflow io_uring/io_uring.c:810 [inline]
 io_req_complete_post io_uring/io_uring.c:937 [inline]
 io_issue_sqe+0x1f1b/0x22c0 io_uring/io_uring.c:1763
 io_wq_submit_work+0xa17/0xeb0 io_uring/io_uring.c:1860
 io_worker_handle_work+0xc04/0x2000 io_uring/io-wq.c:597
 io_wq_worker+0x447/0x1410 io_uring/io-wq.c:651
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 io_req_set_res io_uring/io_uring.h:215 [inline]
 io_recv_finish+0xf10/0x1560 io_uring/net.c:861
 io_recv+0x12ec/0x1ea0 io_uring/net.c:1175
 io_issue_sqe+0x429/0x22c0 io_uring/io_uring.c:1751
 io_wq_submit_work+0xa17/0xeb0 io_uring/io_uring.c:1860
 io_worker_handle_work+0xc04/0x2000 io_uring/io-wq.c:597
 io_wq_worker+0x447/0x1410 io_uring/io-wq.c:651
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3877 [inline]
 slab_alloc_node mm/slub.c:3918 [inline]
 __do_kmalloc_node mm/slub.c:4038 [inline]
 __kmalloc+0x6e4/0x1060 mm/slub.c:4052
 kmalloc include/linux/slab.h:632 [inline]
 io_alloc_async_data+0xc0/0x220 io_uring/io_uring.c:1662
 io_msg_alloc_async io_uring/net.c:166 [inline]
 io_recvmsg_prep_setup io_uring/net.c:725 [inline]
 io_recvmsg_prep+0xbe8/0x1a20 io_uring/net.c:806
 io_init_req io_uring/io_uring.c:2135 [inline]
 io_submit_sqe io_uring/io_uring.c:2182 [inline]
 io_submit_sqes+0x1135/0x2f10 io_uring/io_uring.c:2335
 __do_sys_io_uring_enter io_uring/io_uring.c:3246 [inline]
 __se_sys_io_uring_enter+0x40f/0x3c80 io_uring/io_uring.c:3183
 __x64_sys_io_uring_enter+0x11f/0x1a0 io_uring/io_uring.c:3183
 x64_sys_call+0x2c0/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:427
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 PID: 12521 Comm: iou-wrk-12515 Tainted: G        W          6.9.0-syzkaller-02707-g614da38e2f7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
=====================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/10 03:43 upstream 614da38e2f7a 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in io_issue_sqe
2024/05/27 12:17 upstream 614da38e2f7a a10a183e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in io_issue_sqe
* Struck through repros no longer work on HEAD.