[v6.1] kernel BUG in rxrpc_cleanup_call

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dc5c83b7f5f8 Linux 6.1.178
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=104851b9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=872c04466179833f
dashboard link: https://syzkaller.appspot.com/bug?extid=9de1d2948e7c210ef56e
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/96393e4697a3/disk-dc5c83b7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0d4afce44fab/vmlinux-dc5c83b7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4787e310d875/Image-dc5c83b7.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9de1d2...@syzkaller.appspotmail.com

rxrpc: Assertion failed - 5(0x5) == 11(0xb) is false
------------[ cut here ]------------
kernel BUG at net/rxrpc/call_object.c:689!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 6158 Comm: syz.8.369 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : rxrpc_cleanup_call+0x1b0/0x1c8 net/rxrpc/call_object.c:689
lr : rxrpc_cleanup_call+0x1b0/0x1c8 net/rxrpc/call_object.c:689
sp : ffff800020f27620
x29: ffff800020f27620 x28: ffff0000f1b86220 x27: dfff800000000000
x26: ffff0000f1b85f80 x25: 0000000000000000 x24: 0000000000000001
x23: 0000000000000012 x22: ffff0000f1b866d8 x21: dfff800000000000
x20: 0000000000000005 x19: ffff0000f1b85f80 x18: 0000000000000000
x17: 0000000000000000 x16: ffff800011b90540 x15: 0000000000000002
x14: 0000000000000001 x13: 1ffff000041e4e2c x12: 0000000000080000
x11: 0000000000002b41 x10: ffff800035784000 x9 : 4785e8f30f79cc00
x8 : 4785e8f30f79cc00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800020f270f8 x4 : ffff800015464e80 x3 : ffff80000a92841c
x2 : ffff00019f393d10 x1 : 0000000100000000 x0 : 0000000000000034
Call trace:
rxrpc_cleanup_call+0x1b0/0x1c8 net/rxrpc/call_object.c:689
rxrpc_service_prealloc_one+0x878/0xe80 net/rxrpc/call_accept.c:154
rxrpc_user_charge_accept+0xc0/0x114 net/rxrpc/call_accept.c:458
rxrpc_do_sendmsg+0x70c/0xeb4 net/rxrpc/sendmsg.c:677
rxrpc_sendmsg+0x490/0x70c net/rxrpc/af_rxrpc.c:561
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x588/0x90c net/socket.c:2519
___sys_sendmsg net/socket.c:2573 [inline]
__sys_sendmsg+0x288/0x374 net/socket.c:2602
__do_sys_sendmsg net/socket.c:2611 [inline]
__se_sys_sendmsg net/socket.c:2609 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2609
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: aa1403e2 52800164 52800165 942c267e (d4210000)
---[ end trace 0000000000000000 ]---


---
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[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 674f684f7c61 Linux 5.15.212
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10c031b9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f161cbc9aef65db0
dashboard link: https://syzkaller.appspot.com/bug?extid=3ba459c7faf027b07d6e

compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:

disk image: https://storage.googleapis.com/syzbot-assets/f55be2937b89/disk-674f684f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a19fb0ffc049/vmlinux-674f684f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/365d4529a007/bzImage-674f684f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:

Reported-by: syzbot+3ba459...@syzkaller.appspotmail.com

rxrpc: Assertion failed - 5(0x5) == 11(0xb) is false
------------[ cut here ]------------
kernel BUG at net/rxrpc/call_object.c:689!

invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 5710 Comm: syz.1.400 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:rxrpc_cleanup_call+0x1cf/0x1f0 net/rxrpc/call_object.c:689
Code: e8 46 08 75 f8 41 b8 0b 00 00 00 41 b9 0b 00 00 00 48 c7 c7 e0 8d 34 8b 4c 89 f6 4c 89 f2 48 c7 c1 60 8e 34 8b e8 d1 78 b1 00 <0f> 0b e8 1a 08 75 f8 48 c7 c7 c0 8e 34 8b e8 be 78 b1 00 0f 0b 66
RSP: 0018:ffffc9000329f7d8 EFLAGS: 00010246
RAX: 0000000000000034 RBX: ffff888061f9e4c0 RCX: ba7ac28dcd5c0000
RDX: ffffc90004b99000 RSI: 0000000000002cfb RDI: 0000000000002cfc
RBP: ffff888061f9e4c0 R08: ffff8880b9133d7f R09: 1ffff110172267af
R10: dffffc0000000000 R11: ffffed10172267b0 R12: ffff888061f9e198
R13: 0000000000000012 R14: 0000000000000005 R15: dffffc0000000000
FS: 00007f5a89c6b6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdc89cc9ff8 CR3: 000000005dc4e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
rxrpc_service_prealloc_one+0xa1a/0xef0 net/rxrpc/call_accept.c:154
rxrpc_user_charge_accept+0xb4/0xe0 net/rxrpc/call_accept.c:458
rxrpc_do_sendmsg+0x7c3/0x10c0 net/rxrpc/sendmsg.c:677
sock_sendmsg_nosec net/socket.c:706 [inline]
__sock_sendmsg net/socket.c:718 [inline]
____sys_sendmsg+0x5be/0x8f0 net/socket.c:2446
___sys_sendmsg+0x236/0x2e0 net/socket.c:2500
__sys_sendmsg net/socket.c:2529 [inline]
__do_sys_sendmsg net/socket.c:2538 [inline]
__se_sys_sendmsg+0x1b7/0x2a0 net/socket.c:2536
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5a8ba12e99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5a89c6b028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f5a8bc9afa0 RCX: 00007f5a8ba12e99
RDX: 0000000000000000 RSI: 0000200000000100 RDI: 0000000000000003
RBP: 00007f5a8baa8eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5a8bc9b038 R14: 00007f5a8bc9afa0 R15: 00007ffd10a256d8
</TASK>
Modules linked in:
---[ end trace cbf634d68eed347b ]---
RIP: 0010:rxrpc_cleanup_call+0x1cf/0x1f0 net/rxrpc/call_object.c:689
Code: e8 46 08 75 f8 41 b8 0b 00 00 00 41 b9 0b 00 00 00 48 c7 c7 e0 8d 34 8b 4c 89 f6 4c 89 f2 48 c7 c1 60 8e 34 8b e8 d1 78 b1 00 <0f> 0b e8 1a 08 75 f8 48 c7 c7 c0 8e 34 8b e8 be 78 b1 00 0f 0b 66
RSP: 0018:ffffc9000329f7d8 EFLAGS: 00010246
RAX: 0000000000000034 RBX: ffff888061f9e4c0 RCX: ba7ac28dcd5c0000
RDX: ffffc90004b99000 RSI: 0000000000002cfb RDI: 0000000000002cfc
RBP: ffff888061f9e4c0 R08: ffff8880b9133d7f R09: 1ffff110172267af
R10: dffffc0000000000 R11: ffffed10172267b0 R12: ffff888061f9e198
R13: 0000000000000012 R14: 0000000000000005 R15: dffffc0000000000
FS: 00007f5a89c6b6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056290b92d950 CR3: 000000005dc4e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: dc5c83b7f5f8 Linux 6.1.178
git tree: linux-6.1.y

console output: https://syzkaller.appspot.com/x/log.txt?x=10d50aea580000

kernel config: https://syzkaller.appspot.com/x/.config?x=872c04466179833f
dashboard link: https://syzkaller.appspot.com/bug?extid=9de1d2948e7c210ef56e
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1503d8c6580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1431249e580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/96393e4697a3/disk-dc5c83b7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0d4afce44fab/vmlinux-dc5c83b7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4787e310d875/Image-dc5c83b7.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9de1d2...@syzkaller.appspotmail.com

rxrpc: Assertion failed - 5(0x5) == 11(0xb) is false
------------[ cut here ]------------
kernel BUG at net/rxrpc/call_object.c:689!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:

CPU: 0 PID: 4510 Comm: syz.0.17 Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : rxrpc_cleanup_call+0x1b0/0x1c8 net/rxrpc/call_object.c:689
lr : rxrpc_cleanup_call+0x1b0/0x1c8 net/rxrpc/call_object.c:689

sp : ffff8000214f7620
x29: ffff8000214f7620 x28: ffff0000d7af5ce0 x27: dfff800000000000
x26: ffff0000d7af5a40 x25: 0000000000000000 x24: 0000000000000001
x23: 0000000000000012 x22: ffff0000d7af5718 x21: dfff800000000000
x20: 0000000000000005 x19: ffff0000d7af5a40 x18: 0000000000000000
x17: 0000000000000000 x16: ffff800011b90540 x15: 0000000000000000
x14: 0000000000000001 x13: 1ffff0000429ee2c x12: 0000000000000000
x11: ff00800008315480 x10: 0000000000000000 x9 : f459cb7ade519c00
x8 : f459cb7ade519c00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000214f70f8 x4 : ffff800015464e80 x3 : ffff80000a92841c

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 674f684f7c61 Linux 5.15.212
git tree: linux-5.15.y

console output: https://syzkaller.appspot.com/x/log.txt?x=16f405c1580000

kernel config: https://syzkaller.appspot.com/x/.config?x=f161cbc9aef65db0
dashboard link: https://syzkaller.appspot.com/bug?extid=3ba459c7faf027b07d6e
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10a972a9580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17d592a9580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f55be2937b89/disk-674f684f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a19fb0ffc049/vmlinux-674f684f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/365d4529a007/bzImage-674f684f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3ba459...@syzkaller.appspotmail.com

rxrpc: Assertion failed - 5(0x5) == 11(0xb) is false
------------[ cut here ]------------
kernel BUG at net/rxrpc/call_object.c:689!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN

CPU: 1 PID: 4314 Comm: syz.0.17 Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:rxrpc_cleanup_call+0x1cf/0x1f0 net/rxrpc/call_object.c:689
Code: e8 46 08 75 f8 41 b8 0b 00 00 00 41 b9 0b 00 00 00 48 c7 c7 e0 8d 34 8b 4c 89 f6 4c 89 f2 48 c7 c1 60 8e 34 8b e8 d1 78 b1 00 <0f> 0b e8 1a 08 75 f8 48 c7 c7 c0 8e 34 8b e8 be 78 b1 00 0f 0b 66

RSP: 0018:ffffc9000318f7d8 EFLAGS: 00010246
RAX: 0000000000000034 RBX: ffff88801da49a40 RCX: 7cf0ca4457b8fa00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffff88801da49a40 R08: ffff8880b9133d7f R09: 1ffff110172267af
R10: dffffc0000000000 R11: ffffed10172267b0 R12: ffff88801da49718

R13: 0000000000000012 R14: 0000000000000005 R15: dffffc0000000000

FS: 000055558ed6a500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000200000000000 CR3: 00000000256d1000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
rxrpc_service_prealloc_one+0xa1a/0xef0 net/rxrpc/call_accept.c:154
rxrpc_user_charge_accept+0xb4/0xe0 net/rxrpc/call_accept.c:458
rxrpc_do_sendmsg+0x7c3/0x10c0 net/rxrpc/sendmsg.c:677
sock_sendmsg_nosec net/socket.c:706 [inline]
__sock_sendmsg net/socket.c:718 [inline]
____sys_sendmsg+0x5be/0x8f0 net/socket.c:2446
___sys_sendmsg+0x236/0x2e0 net/socket.c:2500
__sys_sendmsg net/socket.c:2529 [inline]
__do_sys_sendmsg net/socket.c:2538 [inline]
__se_sys_sendmsg+0x1b7/0x2a0 net/socket.c:2536
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0

RIP: 0033:0x7f1e15943e99

Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48

RSP: 002b:00007fff18026f68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1e15bcbfa0 RCX: 00007f1e15943e99

RDX: 0000000000000000 RSI: 0000200000000100 RDI: 0000000000000003

RBP: 00007f1e159d9eaf R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000

R13: 00007f1e15bcbfac R14: 00007f1e15bcbfa0 R15: 00007f1e15bcbfa0
</TASK>
Modules linked in:
---[ end trace 013fe278051f23e1 ]---

RIP: 0010:rxrpc_cleanup_call+0x1cf/0x1f0 net/rxrpc/call_object.c:689
Code: e8 46 08 75 f8 41 b8 0b 00 00 00 41 b9 0b 00 00 00 48 c7 c7 e0 8d 34 8b 4c 89 f6 4c 89 f2 48 c7 c1 60 8e 34 8b e8 d1 78 b1 00 <0f> 0b e8 1a 08 75 f8 48 c7 c7 c0 8e 34 8b e8 be 78 b1 00 0f 0b 66

RSP: 0018:ffffc9000318f7d8 EFLAGS: 00010246
RAX: 0000000000000034 RBX: ffff88801da49a40 RCX: 7cf0ca4457b8fa00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffff88801da49a40 R08: ffff8880b9133d7f R09: 1ffff110172267af
R10: dffffc0000000000 R11: ffffed10172267b0 R12: ffff88801da49718

R13: 0000000000000012 R14: 0000000000000005 R15: dffffc0000000000

FS: 000055558ed6a500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007ffc39d79fa4 CR3: 00000000256d1000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---