=====================================================
BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak-after-free in copy_to_user_iter lib/iov_iter.c:24 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_ubuf include/linux/iov_iter.h:30 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance2 include/linux/iov_iter.h:300 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_iter+0xf0e/0x33f0 lib/iov_iter.c:185
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:30 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:300 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 _copy_to_iter+0xf0e/0x33f0 lib/iov_iter.c:185
 copy_page_to_iter+0x482/0x910 lib/iov_iter.c:362
 copy_folio_to_iter include/linux/uio.h:204 [inline]
 filemap_read+0xcfd/0x2300 mm/filemap.c:2763
 blkdev_read_iter+0x89f/0xb00 block/fops.c:849
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x8ea/0xf90 fs/read_write.c:572
 ksys_read fs/read_write.c:715 [inline]
 __do_sys_read fs/read_write.c:724 [inline]
 __se_sys_read fs/read_write.c:722 [inline]
 __x64_sys_read+0x1fb/0x4d0 fs/read_write.c:722
 x64_sys_call+0x2f9c/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:1
 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:7494
 napi_poll net/core/dev.c:7557 [inline]
 net_rx_action+0xa59/0x1ac0 net/core/dev.c:7684
 handle_softirqs+0x166/0x6e0 kernel/softirq.c:579
 __do_softirq+0x14/0x1b kernel/softirq.c:613

Bytes 202-207 of 512 are uninitialized
Memory access of size 512 starts at ffff88804d09a000
Data copied to user address 00007fe4b9c6b000

CPU: 0 UID: 0 PID: 5965 Comm: udevd Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
=====================================================