WARNING in ceph_con_v2_try_read

Status: upstream: reported C repro on 2026/07/27 06:59
Reported-by: syzbot+0dc33bac91300aa25c34@syzkaller.appspotmail.com
First crash: 21d, last: 19h45m
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2026/08/15 upstream (ToT) 3eb40771c00a C Failed due to an error; will retry later
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in ceph_con_v2_try_read origin:upstream -1 syz, C 4 1d18h 21d 0/3 upstream: reported C repro on 2026/07/27 08:33
upstream WARNING in ceph_con_v2_try_read ceph prio:high -1 syz, C 45 3d02h 17d 0/29 upstream: reported C repro on 2026/07/31 07:09
linux-6.6 WARNING in ceph_con_v2_try_read origin:upstream -1 syz, C 8 15d 21d 0/2 upstream: reported C repro on 2026/07/27 22:59

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4457 at net/ceph/messenger_v2.c:2940 populate_in_iter net/ceph/messenger_v2.c:2940 [inline]
WARNING: CPU: 0 PID: 4457 at net/ceph/messenger_v2.c:2940 ceph_con_v2_try_read+0x5c10/0x5d80 net/ceph/messenger_v2.c:2970
Modules linked in:
CPU: 0 PID: 4457 Comm: kworker/0:7 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
Workqueue: ceph-msgr ceph_con_workfn
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : populate_in_iter net/ceph/messenger_v2.c:2940 [inline]
pc : ceph_con_v2_try_read+0x5c10/0x5d80 net/ceph/messenger_v2.c:2970
lr : populate_in_iter net/ceph/messenger_v2.c:2940 [inline]
lr : ceph_con_v2_try_read+0x5c10/0x5d80 net/ceph/messenger_v2.c:2970
sp : ffff8000215e7780
x29: ffff8000215e7ad0 x28: dfff800000000000 x27: ffff8000215e7860
x26: 00000000000000f8 x25: ffff0000df0a0440 x24: ffff0000df0a0a10
x23: 0000000000000000 x22: 1fffe0001be140d8 x21: ffff0000df0a06c0
x20: ffff0000df0a0428 x19: ffff7000042bcf0c x18: 1fffe00033e7277e
x17: ffff80001537d000 x16: ffff8000082dd244 x15: 0000000000000000
x14: 0000000000000006 x13: 0000000000000000 x12: 0a32762068706563
x11: ff008000117e877c x10: 0000000000000000 x9 : ffff8000117e877c
x8 : ffff0000ceaad400 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
x2 : ffff0000df0a06d8 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 populate_in_iter net/ceph/messenger_v2.c:2940 [inline]
 ceph_con_v2_try_read+0x5c10/0x5d80 net/ceph/messenger_v2.c:2970
 ceph_con_workfn+0x16c/0xdcc net/ceph/messenger.c:1503
 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292
 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439
 kthread+0x254/0x2e0 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850
irq event stamp: 8040
hardirqs last  enabled at (8039): [<ffff8000081ad57c>] __local_bh_enable_ip+0x1f8/0x37c kernel/softirq.c:426
hardirqs last disabled at (8040): [<ffff800011b8c77c>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (8038): [<ffff80000fe7fe84>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (8038): [<ffff80000fe7fe84>] release_sock+0x16c/0x1bc net/core/sock.c:3531
softirqs last disabled at (8036): [<ffff80000fe7fd4c>] spin_lock_bh include/linux/spinlock.h:356 [inline]
softirqs last disabled at (8036): [<ffff80000fe7fd4c>] release_sock+0x34/0x1bc net/core/sock.c:3518
---[ end trace 0000000000000000 ]---
libceph: mon0 (2)127.0.0.1:6789 read processing error

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/27 07:45 linux-6.1.y dc5c83b7f5f8 492bab15 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ceph_con_v2_try_read
2026/07/28 00:22 linux-6.1.y dc5c83b7f5f8 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ceph_con_v2_try_read
2026/08/17 07:46 linux-6.1.y e4f7d8be268e 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ceph_con_v2_try_read
2026/08/17 07:45 linux-6.1.y e4f7d8be268e 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ceph_con_v2_try_read
2026/07/27 20:12 linux-6.1.y dc5c83b7f5f8 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ceph_con_v2_try_read
2026/07/27 20:12 linux-6.1.y dc5c83b7f5f8 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ceph_con_v2_try_read
2026/07/27 07:01 linux-6.1.y dc5c83b7f5f8 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ceph_con_v2_try_read
2026/07/27 06:58 linux-6.1.y dc5c83b7f5f8 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ceph_con_v2_try_read
* Struck through repros no longer work on HEAD.