Subject: [syzbot] [net?] [virt?] [io-uring?] [kvm?] BUG: soft lockup in vsock_connect

From: syzbot <[email-masked]>
Date: Thu, 23 Mar 2023 17:52:41 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    fe15c26ee26e Linux 6.3-rc1
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=1577c97ec80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7573cbcd881a88c9
dashboard link: https://syzkaller.appspot.com/bug?extid=0bc015ebddc291a97116
compiler:       Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1077c996c80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17e38929c80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/89d41abd07bd/disk-fe15c26e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fa75f5030ade/vmlinux-fe15c26e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/590d0f5903ee/Image-fe15c26e.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

watchdog: BUG: soft lockup - CPU#0 stuck for 27s! [syz-executor244:6747]
Modules linked in:
irq event stamp: 6033
hardirqs last  enabled at (6032): [<ffff8000124604ac>] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:84 [inline]
hardirqs last  enabled at (6032): [<ffff8000124604ac>] exit_to_kernel_mode+0xe8/0x118 arch/arm64/kernel/entry-common.c:94
hardirqs last disabled at (6033): [<ffff80001245e188>] __el1_irq arch/arm64/kernel/entry-common.c:468 [inline]
hardirqs last disabled at (6033): [<ffff80001245e188>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:486
softirqs last  enabled at (616): [<ffff80001066ca80>] spin_unlock_bh include/linux/spinlock.h:395 [inline]
softirqs last  enabled at (616): [<ffff80001066ca80>] lock_sock_nested+0xe8/0x138 net/core/sock.c:3480
softirqs last disabled at (618): [<ffff8000122dbcfc>] spin_lock_bh include/linux/spinlock.h:355 [inline]
softirqs last disabled at (618): [<ffff8000122dbcfc>] virtio_transport_purge_skbs+0x11c/0x500 net/vmw_vsock/virtio_transport_common.c:1372
CPU: 0 PID: 6747 Comm: syz-executor244 Not tainted 6.3.0-rc1-syzkaller-gfe15c26ee26e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __sanitizer_cov_trace_pc+0xc/0x8c kernel/kcov.c:203
lr : virtio_transport_purge_skbs+0x19c/0x500 net/vmw_vsock/virtio_transport_common.c:1374
sp : ffff80001e787890
x29: ffff80001e7879e0 x28: 1ffff00003cf0f2a x27: ffff80001a487a60
x26: ffff80001e787950 x25: ffff0000ce2d3b80 x24: ffff80001a487a78
x23: 1ffff00003490f4c x22: ffff80001a29c1a8 x21: dfff800000000000
x20: ffff80001a487a60 x19: ffff80001e787940 x18: 1fffe000368951b6
x17: ffff800015cdd000 x16: ffff8000085110b0 x15: 0000000000000000
x14: 1ffff00002b9c0b2 x13: dfff800000000000 x12: ffff700003cf0efc
x11: ff808000122dbee8 x10: 0000000000000000 x9 : ffff8000122dbee8
x8 : ffff0000ce511b40 x7 : ffff8000122dbcfc x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80000832d758
x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 get_current arch/arm64/include/asm/current.h:19 [inline]
 __sanitizer_cov_trace_pc+0xc/0x8c kernel/kcov.c:206
 vsock_loopback_cancel_pkt+0x28/0x3c net/vmw_vsock/vsock_loopback.c:48
 vsock_transport_cancel_pkt net/vmw_vsock/af_vsock.c:1284 [inline]
 vsock_connect+0x6b8/0xaec net/vmw_vsock/af_vsock.c:1426
 __sys_connect_file net/socket.c:2004 [inline]
 __sys_connect+0x268/0x290 net/socket.c:2021
 __do_sys_connect net/socket.c:2031 [inline]
 __se_sys_connect net/socket.c:2028 [inline]
 __arm64_sys_connect+0x7c/0x94 net/socket.c:2028
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591

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