[syzbot] [wpan?] KMSAN: uninit-value in crc_ccitt (3)

[syzbot <syzbot+29d74bf076f40407a62a@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    b236920731dd Merge tag 'rust-fixes-6.17-2' of git://git.ke..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1451fa42580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1ee07385471829e7
dashboard link: https://syzkaller.appspot.com/bug?extid=29d74bf076f40407a62a
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a67f2d67e93e/disk-b2369207.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/59e5d1fccb4a/vmlinux-b2369207.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f501250ee790/bzImage-b2369207.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+29d74bf076f40407a62a@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in crc_ccitt_byte include/linux/crc-ccitt.h:13 [inline]
BUG: KMSAN: uninit-value in crc_ccitt+0x21e/0x2a0 lib/crc/crc-ccitt.c:60
 crc_ccitt_byte include/linux/crc-ccitt.h:13 [inline]
 crc_ccitt+0x21e/0x2a0 lib/crc/crc-ccitt.c:60
 ieee802154_tx+0x2c4/0x7e0 net/mac802154/tx.c:74
 ieee802154_hot_tx net/mac802154/tx.c:207 [inline]
 ieee802154_subif_start_xmit+0x183/0x290 net/mac802154/tx.c:239
 __netdev_start_xmit include/linux/netdevice.h:5222 [inline]
 netdev_start_xmit include/linux/netdevice.h:5231 [inline]
 xmit_one net/core/dev.c:3839 [inline]
 dev_hard_start_xmit+0x22c/0xa30 net/core/dev.c:3855
 sch_direct_xmit+0x3b2/0xcf0 net/sched/sch_generic.c:344
 __dev_xmit_skb net/core/dev.c:4114 [inline]
 __dev_queue_xmit+0x3588/0x5e60 net/core/dev.c:4691
 dev_queue_xmit include/linux/netdevice.h:3361 [inline]
 dgram_sendmsg+0xcdb/0x16d0 net/ieee802154/socket.c:689
 ieee802154_sock_sendmsg+0x8f/0xd0 net/ieee802154/socket.c:96
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x330/0x3d0 net/socket.c:729
 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2614
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2703
 x64_sys_call+0x1dfd/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable rf created at:
 __schedule+0x3b/0x7790 kernel/sched/core.c:6827
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x17d/0x3c0 kernel/sched/core.c:7058

CPU: 0 UID: 0 PID: 7766 Comm: syz.2.4465 Tainted: G        W           syzkaller #0 PREEMPT(none) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
=====================================================


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