[v6.1] BUG: soft lockup in sys_sendmsg (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 347385861c50 Linux 6.1.84
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1562a29d180000
kernel config: https://syzkaller.appspot.com/x/.config?x=c6572e59ce99583c
dashboard link: https://syzkaller.appspot.com/bug?extid=c7533f9d3c8cc92c04e7
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1534258d180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12d25d29180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/101d17869fc3/disk-34738586.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1fd47dc155f3/vmlinux-34738586.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3a82e916ef21/Image-34738586.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c7533f...@syzkaller.appspotmail.com

watchdog: BUG: soft lockup - CPU#0 stuck for 27s! [syz-executor327:4299]
Modules linked in:
irq event stamp: 35843731
hardirqs last enabled at (35843730): [<ffff8000081c784c>] __local_bh_enable_ip+0x230/0x470 kernel/softirq.c:401
hardirqs last disabled at (35843731): [<ffff800012151f7c>] __el1_irq arch/arm64/kernel/entry-common.c:468 [inline]
hardirqs last disabled at (35843731): [<ffff800012151f7c>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:486
softirqs last enabled at (740): [<ffff800011efa314>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last enabled at (740): [<ffff800011efa314>] batadv_tvlv_container_register+0x1fc/0x368 net/batman-adv/tvlv.c:258
softirqs last disabled at (744): [<ffff800011ef1d44>] spin_lock_bh include/linux/spinlock.h:356 [inline]
softirqs last disabled at (744): [<ffff800011ef1d44>] batadv_tt_local_resize_to_mtu+0x60/0x150 net/batman-adv/translation-table.c:3949
CPU: 0 PID: 4299 Comm: syz-executor327 Not tainted 6.1.84-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : should_resched arch/arm64/include/asm/preempt.h:79 [inline]
pc : __local_bh_enable_ip+0x238/0x470 kernel/softirq.c:403
lr : __local_bh_enable_ip+0x230/0x470 kernel/softirq.c:401
sp : ffff80001e117110
x29: ffff80001e117120 x28: ffff700003c22e68 x27: ffff80001e117450
x26: ffff0000d61a0640 x25: ffff0000c33ab308 x24: 0000000000000001
x23: 1fffe00019067001 x22: dfff800000000000 x21: ffff800011ef2098
x20: 0000000000000202 x19: ffff0000c8338008 x18: ffff80001e116780
x17: 77656e2074696620 x16: ffff800008305ec4 x15: 0000000000000000
x14: 1ffff00002b080b0 x13: dfff800000000000 x12: 0000000000000003
x11: 0000000000ff0100 x10: 0000000000000003 x9 : 0000000000000000
x8 : 00000000000000e0 x7 : ffff800011ef1f30 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000002 x1 : ffff8000122ac6e0 x0 : ffff80019ebc9000
Call trace:
arch_local_irq_enable arch/arm64/include/asm/irqflags.h:35 [inline]
__local_bh_enable_ip+0x238/0x470 kernel/softirq.c:401
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x48/0x58 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_tt_local_purge+0x264/0x2e8 net/batman-adv/translation-table.c:1356
batadv_tt_local_resize_to_mtu+0x9c/0x150 net/batman-adv/translation-table.c:3956
batadv_update_min_mtu+0x74/0xa4 net/batman-adv/hard-interface.c:650
batadv_netlink_set_mesh+0x50c/0xf3c net/batman-adv/netlink.c:500
genl_family_rcv_msg_doit net/netlink/genetlink.c:756 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:833 [inline]
genl_rcv_msg+0x948/0xc2c net/netlink/genetlink.c:850
netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2508
genl_rcv+0x38/0x50 net/netlink/genetlink.c:861
netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
netlink_unicast+0x65c/0x898 net/netlink/af_netlink.c:1352
netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1874
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x55c/0x848 net/socket.c:2514
___sys_sendmsg net/socket.c:2568 [inline]
__sys_sendmsg+0x26c/0x33c net/socket.c:2597
__do_sys_sendmsg net/socket.c:2606 [inline]
__se_sys_sendmsg net/socket.c:2604 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2604
__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+0x64/0x218 arch/arm64/kernel/syscall.c:206
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+0x18c/0x190 arch/arm64/kernel/entry.S:585


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