Re: [syzbot] [net?] kernel BUG in __sock_sendmsg

[syzbot <syzbot+58c03971700330ce14d8@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in __sock_sendmsg

------------[ cut here ]------------
kernel BUG at net/socket.c:733!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 UID: 0 PID: 3938 Comm: syz.0.15 Not tainted 6.11.0-rc3-syzkaller-gc3f2d783a459 #0
Hardware name: linux,dummy-virt (DT)
pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : sock_sendmsg_nosec net/socket.c:733 [inline]
pc : sock_sendmsg_nosec net/socket.c:728 [inline]
pc : __sock_sendmsg+0x5c/0x60 net/socket.c:745
lr : sock_sendmsg_nosec net/socket.c:730 [inline]
lr : __sock_sendmsg+0x54/0x60 net/socket.c:745
sp : ffff80008960bb30
x29: ffff80008960bb30 x28: f8f00000054a4900 x27: 0000000000000000
x26: ffff80008960bbc0 x25: ffff80008960bbc0 x24: 0000000000000000
x23: fbf0000005f33740 x22: 0000000000000000 x21: ffff80008960bd90
x20: fbf0000005f33740 x19: ffff80008960bd90 x18: 0000000000000001
x17: 0000000000000000 x16: 0000000000000000 x15: 000000002002ffaf
x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: ffff800081585b20 x9 : ffff8000815b4b18
x8 : 0000000000000000 x7 : 000000000000003f x6 : 0000000000000000
x5 : 00000000000007e0 x4 : fff07ffffd239000 x3 : f8f00000054a4900
x2 : 0000000000000000 x1 : 0000000000000000 x0 : 00000000fffffdef
Call trace:
 sock_sendmsg_nosec net/socket.c:733 [inline]
 __sock_sendmsg+0x5c/0x60 net/socket.c:745
 ____sys_sendmsg+0x274/0x2ac net/socket.c:2597
 ___sys_sendmsg+0xac/0x100 net/socket.c:2651
 __sys_sendmsg+0x84/0xe0 net/socket.c:2680
 __do_sys_sendmsg net/socket.c:2689 [inline]
 __se_sys_sendmsg net/socket.c:2687 [inline]
 __arm64_sys_sendmsg+0x24/0x30 net/socket.c:2687
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x48/0x110 arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151
 el0_svc+0x34/0xec arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598
Code: f9404463 d63f0060 3108441f 54fffe81 (d4210000) 
---[ end trace 0000000000000000 ]---


Tested on:

commit:         c3f2d783 Merge tag 'mm-hotfixes-stable-2024-08-17-19-3..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14d277c5980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9f3e2eb337834cdf
dashboard link: https://syzkaller.appspot.com/bug?extid=58c03971700330ce14d8
compiler:       aarch64-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

Note: no patches were applied.