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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]
 kfree_skb include/linux/skbuff.h:1284 [inline]
 mrp_rcv+0x2a6d/0x2b60 net/802/mrp.c:827
 __netif_receive_skb_one_core net/core/dev.c:5979 [inline]
 __netif_receive_skb+0x474/0xac0 net/core/dev.c:6092
 process_backlog+0x485/0xa00 net/core/dev.c:6444
 __napi_poll+0xdd/0x8a0 net/core/dev.c:7489
 napi_poll net/core/dev.c:7552 [inline]
 net_rx_action+0xa59/0x1ac0 net/core/dev.c:7679
 handle_softirqs+0x166/0x6e0 kernel/softirq.c:579
 run_ksoftirqd+0x29/0x50 kernel/softirq.c:968
 smpboot_thread_fn+0x56c/0xa30 kernel/smpboot.c:160
 kthread+0xd59/0xf00 kernel/kthread.c:463
 ret_from_fork+0x1e3/0x310 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Bytes 4-1955 of 1956 are uninitialized
Memory access of size 1956 starts at ffff888020dbc800
Data copied to user address 0000200000000080

CPU: 1 UID: 0 PID: 11294 Comm: syz.3.1389 Tainted: G        W           6.17.0-rc1-syzkaller-00038-g0cc53520e68b #0 PREEMPT(none) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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