WARNING in ceph_con_v2_try_read

Status: upstream: reported C repro on 2026/07/27 08:33
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+8d72882015436ebb4a2d@syzkaller.appspotmail.com
First crash: 11d, last: 11d
Bug presence (1)
Date Name Commit Repro Result
2026/08/02 upstream (ToT) 2d2338c93da7 C [report] WARNING in ceph_con_v2_try_read
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in ceph_con_v2_try_read -1 syz, C 6 10d 11d 0/3 upstream: reported C repro on 2026/07/27 06:59
upstream WARNING in ceph_con_v2_try_read ceph prio:high -1 syz, C 41 4d16h 7d15h 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 4d21h 11d 0/2 upstream: reported C repro on 2026/07/27 22:59

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 1325 at net/ceph/messenger_v2.c:2839 populate_in_iter net/ceph/messenger_v2.c:2839 [inline]
WARNING: CPU: 1 PID: 1325 at net/ceph/messenger_v2.c:2839 ceph_con_v2_try_read+0x6e45/0x6fc0 net/ceph/messenger_v2.c:2869
Modules linked in:
CPU: 1 PID: 1325 Comm: kworker/1:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: ceph-msgr ceph_con_workfn
RIP: 0010:populate_in_iter net/ceph/messenger_v2.c:2839 [inline]
RIP: 0010:ceph_con_v2_try_read+0x6e45/0x6fc0 net/ceph/messenger_v2.c:2869
Code: 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 05 f7 ea f7 48 c7 c7 40 f5 3f 8b 89 de e8 47 1f 27 00 0f 0b e9 29 ff ff ff e8 eb f6 ea f7 <0f> 0b 41 bf c3 ff ff ff e9 1d ff ff ff e8 d9 f6 ea f7 0f 0b 41 bf
RSP: 0018:ffffc900051c7760 EFLAGS: 00010293
RAX: ffffffff898e0a95 RBX: 0000000000000000 RCX: ffff888023031dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900051c7bb8 R08: ffff88807aca46b7 R09: ffff88807aca46ab
R10: dffffc0000000000 R11: ffffed100f5948d7 R12: ffff88807aca4808
R13: dffffc0000000000 R14: ffff88807aca46b8 R15: 1ffff1100f59495b
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0f918a1ff8 CR3: 0000000024e60000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ceph_con_workfn+0x1ed/0x1110 net/ceph/messenger.c:1528
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/27 09:36 linux-5.15.y 674f684f7c61 492bab15 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ceph_con_v2_try_read
2026/07/27 21:51 linux-5.15.y 674f684f7c61 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ceph_con_v2_try_read
2026/07/27 10:50 linux-5.15.y 674f684f7c61 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ceph_con_v2_try_read
2026/07/27 08:32 linux-5.15.y 674f684f7c61 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ceph_con_v2_try_read
* Struck through repros no longer work on HEAD.