===================================================== BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline] BUG: KMSAN: kernel-infoleak-after-free in _inline_copy_to_user include/linux/uaccess.h:196 [inline] BUG: KMSAN: kernel-infoleak-after-free in _copy_to_user+0xcc/0x120 lib/usercopy.c:26 instrument_copy_to_user include/linux/instrumented.h:114 [inline] _inline_copy_to_user include/linux/uaccess.h:196 [inline] _copy_to_user+0xcc/0x120 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:225 [inline] do_insn_ioctl+0x59c/0x6d0 drivers/comedi/comedi_fops.c:1678 comedi_unlocked_ioctl+0xa5e/0x1f60 drivers/comedi/comedi_fops.c:2303 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl+0x23c/0x400 fs/ioctl.c:584 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:584 x64_sys_call+0x1cbc/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:17 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 Uninit was created at: slab_free_hook mm/slub.c:2343 [inline] slab_free mm/slub.c:4680 [inline] kfree+0x252/0xec0 mm/slub.c:4879 skb_kfree_head net/core/skbuff.c:1047 [inline] skb_free_head+0x1b5/0x3a0 net/core/skbuff.c:1059 skb_release_data+0x9f7/0xac0 net/core/skbuff.c:1086 skb_release_all net/core/skbuff.c:1151 [inline] __kfree_skb+0x6b/0x260 net/core/skbuff.c:1165 sk_skb_reason_drop+0x126/0x440 net/core/skbuff.c:1203 kfree_skb_reason include/linux/skbuff.h:1275 [inline] __netif_receive_skb_core+0x6642/0x6df0 net/core/dev.c:5953 __netif_receive_skb_one_core net/core/dev.c:5977 [inline] __netif_receive_skb+0xcc/0xac0 net/core/dev.c:6092 process_backlog+0x485/0xa00 net/core/dev.c:6444 __napi_poll+0xda/0x8a0 net/core/dev.c:7497 napi_poll net/core/dev.c:7560 [inline] net_rx_action+0xa59/0x1ac0 net/core/dev.c:7687 handle_softirqs+0x166/0x6e0 kernel/softirq.c:579 __do_softirq+0x14/0x1b kernel/softirq.c:613 Bytes 4-583 of 584 are uninitialized Memory access of size 584 starts at ffff888116017c00 CPU: 0 UID: 0 PID: 17107 Comm: syz.4.3394 Not tainted 6.16.0-syzkaller-11952-g6e64f4580381 #0 PREEMPT(none) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 =====================================================