syzbot


WARNING in kcm_write_msgs

Status: upstream: reported C repro on 2024/04/23 04:47
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+b490d5e95bd8ecce1aeb@syzkaller.appspotmail.com
First crash: 63d, last: 62d
Bug presence (2)
Date Name Commit Repro Result
2024/04/24 linux-5.15.y (ToT) c52b9710c83d C [report] WARNING in kcm_write_msgs
2024/04/24 upstream (ToT) 9d1ddab261f3 C Didn't crash
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in kcm_write_msgs origin:upstream C 2 15d 210d 0/3 upstream: reported C repro on 2023/11/28 05:07
upstream WARNING in kcm_write_msgs net C done 515 9d01h 1559d 0/27 upstream: reported C repro on 2020/03/19 07:10
linux-4.14 WARNING in kcm_write_msgs C inconclusive 2 529d 1535d 0/1 upstream: reported C repro on 2020/04/12 04:13
linux-4.19 WARNING in kcm_write_msgs C error 8 523d 1548d 0/1 upstream: reported C repro on 2020/03/30 19:34
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2024/04/24 15:54 26m fix candidate upstream error job log (0)

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 3972 at net/kcm/kcmsock.c:633 kcm_write_msgs+0x800/0xfc0
Modules linked in:
CPU: 1 PID: 3972 Comm: syz-executor258 Not tainted 5.15.156-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
pstate: 80401005 (Nzcv daif +PAN -UAO -TCO -DIT +SSBS BTYPE=--)
pc : kcm_write_msgs+0x800/0xfc0
lr : kcm_write_msgs+0x7fc/0xfc0 net/kcm/kcmsock.c:633
sp : ffff80001cb37620
x29: ffff80001cb376a0 x28: 00000000ffffffea x27: dfff800000000000
x26: 0000000000220000 x25: ffff0000df914800 x24: ffff0000d7ee8000
x23: ffff0000d9f358c0 x22: ffff0000d9f35a00 x21: 0000000000000011
x20: ffff0000da37b400 x19: 0000000000000000 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000084c4340 x15: 0000000000000001
x14: 1ffff0000292806a x13: dfff800000000000 x12: 0000000000000003
x11: 0000000000000000 x10: 0000000000000000 x9 : ffff0000d5949b40
x8 : ffff800010f302d0 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff80000804685c
x2 : 0000000000000006 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 kcm_write_msgs+0x800/0xfc0
 kcm_sendmsg+0x1918/0x1ed8 net/kcm/kcmsock.c:1039
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 sock_write_iter+0x2b0/0x3f8 net/socket.c:1079
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x87c/0xb3c fs/read_write.c:594
 ksys_write+0x15c/0x26c fs/read_write.c:647
 __do_sys_write fs/read_write.c:659 [inline]
 __se_sys_write fs/read_write.c:656 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:656
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
irq event stamp: 17798
hardirqs last  enabled at (17797): [<ffff8000081b5d1c>] __local_bh_enable_ip+0x230/0x470 kernel/softirq.c:388
hardirqs last disabled at (17798): [<ffff800011991e80>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:396
softirqs last  enabled at (17796): [<ffff80000fd58e3c>] spin_unlock_bh include/linux/spinlock.h:408 [inline]
softirqs last  enabled at (17796): [<ffff80000fd58e3c>] release_sock+0x1e4/0x270 net/core/sock.c:3276
softirqs last disabled at (17794): [<ffff80000fd58c94>] spin_lock_bh include/linux/spinlock.h:368 [inline]
softirqs last disabled at (17794): [<ffff80000fd58c94>] release_sock+0x3c/0x270 net/core/sock.c:3263
---[ end trace f599c1dd0ca5049e ]---
KCM: Hard failure on kcm_write_msgs

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/23 04:47 linux-5.15.y c52b9710c83d 36c961ad .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in kcm_write_msgs
* Struck through repros no longer work on HEAD.