KCSAN: data-race in p9_fd_create / p9_fd_create (2)

Status: auto-obsoleted due to no activity on 2023/09/27 01:59
Subsystems: v9fs
[Documentation on labels]
Reported-by: syzbot+e441aeeb422763cc5511@syzkaller.appspotmail.com
First crash: 1119d, last: 1119d
▶ ▼ Discussions (8)
Title Replies (including bot) Last reply
[PATCH AUTOSEL 5.10 5/5] 9p/trans_fd: Annotate data-racy writes to file::f_flags 1 (1) 2023/11/07 23:25
[PATCH AUTOSEL 5.15 5/6] 9p/trans_fd: Annotate data-racy writes to file::f_flags 1 (1) 2023/11/07 23:24
[PATCH AUTOSEL 6.1 10/11] 9p/trans_fd: Annotate data-racy writes to file::f_flags 1 (1) 2023/11/07 23:24
[PATCH AUTOSEL 6.5 17/18] 9p/trans_fd: Annotate data-racy writes to file::f_flags 1 (1) 2023/11/07 23:23
[PATCH AUTOSEL 6.6 17/18] 9p/trans_fd: Annotate data-racy writes to file::f_flags 1 (1) 2023/11/07 23:22
[PATCH v2 1/3] 9p/trans_fd: Annotate data-racy writes to file::f_flags 1 (1) 2023/10/25 10:34
[PATCH 1/3] 9p: Annotate data-racy writes to file::f_flags on fd mount 5 (5) 2023/10/24 11:58
[syzbot] [net?] [v9fs?] KCSAN: data-race in p9_fd_create / p9_fd_create (2) 4 (5) 2023/08/30 07:59
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in p9_fd_create / p9_fd_create v9fs 6 1 1185d 1185d 0/29 auto-obsoleted due to no activity on 2023/07/23 06:35

Sample crash report:
==================================================================
BUG: KCSAN: data-race in p9_fd_create / p9_fd_create

read-write to 0xffff888130fb3d48 of 4 bytes by task 15599 on cpu 0:
 p9_fd_open net/9p/trans_fd.c:842 [inline]
 p9_fd_create+0x210/0x250 net/9p/trans_fd.c:1092
 p9_client_create+0x595/0xa70 net/9p/client.c:1010
 v9fs_session_init+0xf9/0xd90 fs/9p/v9fs.c:410
 v9fs_mount+0x69/0x630 fs/9p/vfs_super.c:123
 legacy_get_tree+0x74/0xd0 fs/fs_context.c:611
 vfs_get_tree+0x51/0x190 fs/super.c:1519
 do_new_mount+0x203/0x660 fs/namespace.c:3335
 path_mount+0x496/0xb30 fs/namespace.c:3662
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff888130fb3d48 of 4 bytes by task 15563 on cpu 1:
 p9_fd_open net/9p/trans_fd.c:842 [inline]
 p9_fd_create+0x210/0x250 net/9p/trans_fd.c:1092
 p9_client_create+0x595/0xa70 net/9p/client.c:1010
 v9fs_session_init+0xf9/0xd90 fs/9p/v9fs.c:410
 v9fs_mount+0x69/0x630 fs/9p/vfs_super.c:123
 legacy_get_tree+0x74/0xd0 fs/fs_context.c:611
 vfs_get_tree+0x51/0x190 fs/super.c:1519
 do_new_mount+0x203/0x660 fs/namespace.c:3335
 path_mount+0x496/0xb30 fs/namespace.c:3662
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00008002 -> 0x00008802

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15563 Comm: syz-executor.3 Not tainted 6.5.0-rc7-syzkaller-00013-g53663f4103ff #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/23 01:58 upstream 53663f4103ff b81ca3f6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in p9_fd_create / p9_fd_create
* Struck through repros no longer work on HEAD.