Hello, syzbot found the following issue on:
HEAD commit: e8c2f9fdadee Merge tag 'for-7.1/hpfs-fixes' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10883b06580000 kernel config: https://syzkaller.appspot.com/x/.config?x=91978e795dcd971b dashboard link: https://syzkaller.appspot.com/bug?extid=f13c19f75e1097abd116 compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/6d28568f6ffa/disk-e8c2f9fd.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/68a9eec5e7f1/vmlinux-e8c2f9fd.xz kernel image: https://storage.googleapis.com/syzbot-assets/e6a7381a5e55/bzImage-e8c2f9fd.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: [email protected] dev_queue_xmit include/linux/netdevice.h:3418 [inline] tx+0xb6/0x440 drivers/block/aoe/aoenet.c:62 kthread+0x17d/0x370 drivers/block/aoe/aoecmd.c:1241 kthread+0x53a/0x5f0 kernel/kthread.c:436 ret_from_fork+0x20f/0x8d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> ---[ end trace 0000000000000000 ]--- ===================================================== BUG: KMSAN: uninit-value in lowpan_header net/ieee802154/6lowpan/tx.c:240 [inline] BUG: KMSAN: uninit-value in lowpan_xmit+0xa6b/0x1d00 net/ieee802154/6lowpan/tx.c:282 lowpan_header net/ieee802154/6lowpan/tx.c:240 [inline] lowpan_xmit+0xa6b/0x1d00 net/ieee802154/6lowpan/tx.c:282 __netdev_start_xmit include/linux/netdevice.h:5368 [inline] netdev_start_xmit include/linux/netdevice.h:5377 [inline] xmit_one net/core/dev.c:3888 [inline] dev_hard_start_xmit+0x22f/0xa80 net/core/dev.c:3904 __dev_queue_xmit+0x2990/0x5a00 net/core/dev.c:4870 dev_queue_xmit include/linux/netdevice.h:3418 [inline] tx+0xb6/0x440 drivers/block/aoe/aoenet.c:62 kthread+0x17d/0x370 drivers/block/aoe/aoecmd.c:1241 kthread+0x53a/0x5f0 kernel/kthread.c:436 ret_from_fork+0x20f/0x8d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Uninit was stored to memory at: lowpan_header net/ieee802154/6lowpan/tx.c:231 [inline] lowpan_xmit+0x68f/0x1d00 net/ieee802154/6lowpan/tx.c:282 __netdev_start_xmit include/linux/netdevice.h:5368 [inline] netdev_start_xmit include/linux/netdevice.h:5377 [inline] xmit_one net/core/dev.c:3888 [inline] dev_hard_start_xmit+0x22f/0xa80 net/core/dev.c:3904 __dev_queue_xmit+0x2990/0x5a00 net/core/dev.c:4870 dev_queue_xmit include/linux/netdevice.h:3418 [inline] tx+0xb6/0x440 drivers/block/aoe/aoenet.c:62 kthread+0x17d/0x370 drivers/block/aoe/aoecmd.c:1241 kthread+0x53a/0x5f0 kernel/kthread.c:436 ret_from_fork+0x20f/0x8d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Uninit was created at: slab_post_alloc_hook mm/slub.c:4577 [inline] slab_alloc_node mm/slub.c:4899 [inline] kmem_cache_alloc_node_noprof+0x3cd/0x12c0 mm/slub.c:4951 kmalloc_reserve net/core/skbuff.c:613 [inline] __alloc_skb+0x855/0x1190 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] new_skb+0x4a/0x550 drivers/block/aoe/aoecmd.c:66 aoecmd_cfg_pkts drivers/block/aoe/aoecmd.c:430 [inline] aoecmd_cfg+0x2c2/0xb70 drivers/block/aoe/aoecmd.c:1374 discover_timer+0x64/0x80 drivers/block/aoe/aoemain.c:25 call_timer_fn+0x4c/0x510 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x80a/0xdb0 kernel/time/timer.c:2386 run_timer_base kernel/time/timer.c:2395 [inline] run_timer_softirq+0x3a/0x70 kernel/time/timer.c:2405 handle_softirqs+0x171/0x7b0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x9a/0x1e0 kernel/softirq.c:735 irq_exit_rcu+0x12/0x20 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x84/0x90 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:697 CPU: 0 UID: 0 PID: 1310 Comm: aoe_tx0 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 ===================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at [email protected]. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
