Re: [syzbot] [wpan?] KMSAN: uninit-value in ieee802154_hdr_push (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KMSAN: uninit-value in ieee802154_hdr_push

=====================================================
BUG: KMSAN: uninit-value in ieee802154_hdr_push_sechdr net/ieee802154/header_ops.c:54 [inline]
BUG: KMSAN: uninit-value in ieee802154_hdr_push+0x9ac/0xa30 net/ieee802154/header_ops.c:108
ieee802154_hdr_push_sechdr net/ieee802154/header_ops.c:54 [inline]
ieee802154_hdr_push+0x9ac/0xa30 net/ieee802154/header_ops.c:108
ieee802154_header_create+0x812/0xb60 net/mac802154/iface.c:402
wpan_dev_hard_header include/net/cfg802154.h:525 [inline]
dgram_sendmsg+0xb40/0x16d0 net/ieee802154/socket.c:677
ieee802154_sock_sendmsg+0x92/0xd0 net/ieee802154/socket.c:96
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x333/0x3d0 net/socket.c:742
____sys_sendmsg+0x7f5/0xcf0 net/socket.c:2592
___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2681
x64_sys_call+0x1c60/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:47
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
ieee802154_hdr_push_sechdr net/ieee802154/header_ops.c:54 [inline]
ieee802154_hdr_push+0x9a5/0xa30 net/ieee802154/header_ops.c:108
ieee802154_header_create+0x812/0xb60 net/mac802154/iface.c:402
wpan_dev_hard_header include/net/cfg802154.h:525 [inline]
dgram_sendmsg+0xb40/0x16d0 net/ieee802154/socket.c:677
ieee802154_sock_sendmsg+0x92/0xd0 net/ieee802154/socket.c:96
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x333/0x3d0 net/socket.c:742
____sys_sendmsg+0x7f5/0xcf0 net/socket.c:2592
___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2681
x64_sys_call+0x1c60/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:47
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable hdr created at:
ieee802154_header_create+0x4e/0xb60 net/mac802154/iface.c:366
wpan_dev_hard_header include/net/cfg802154.h:525 [inline]
dgram_sendmsg+0xb40/0x16d0 net/ieee802154/socket.c:677

CPU: 1 UID: 0 PID: 6600 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
=====================================================


Tested on:

commit: 4a298a43 Merge tag 'smp-urgent-2025-12-12' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=118609c2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=47c3d24c6e93e95d
dashboard link: https://syzkaller.appspot.com/bug?extid=60a66d44892b66b56545
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch: https://syzkaller.appspot.com/x/patch.diff?x=17099e1a580000

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+60a66d...@syzkaller.appspotmail.com
Tested-by: syzbot+60a66d...@syzkaller.appspotmail.com

Tested on:

commit: 4a298a43 Merge tag 'smp-urgent-2025-12-12' of git://gi..
git tree: upstream

console output: https://syzkaller.appspot.com/x/log.txt?x=14f47e1a580000

kernel config: https://syzkaller.appspot.com/x/.config?x=47c3d24c6e93e95d
dashboard link: https://syzkaller.appspot.com/bug?extid=60a66d44892b66b56545
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

patch: https://syzkaller.appspot.com/x/patch.diff?x=171971b4580000

Note: testing is done by a robot and is best-effort only.