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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 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:302 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance include/linux/iov_iter.h:330 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_iter+0xef3/0x33f0 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:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 _copy_to_iter+0xef3/0x33f0 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+0x1cda/0x2300 mm/filemap.c:2799
 blkdev_read_iter+0x89f/0xb00 block/fops.c:859
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x8ed/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/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 memcpy_to_iter lib/iov_iter.c:65 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:306 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 _copy_to_iter+0x130f/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]
 shmem_file_read_iter+0x904/0x1140 mm/shmem.c:3412
 lo_rw_aio+0x1268/0x1590 drivers/block/loop.c:-1
 do_req_filebacked drivers/block/loop.c:-1 [inline]
 loop_handle_cmd drivers/block/loop.c:1923 [inline]
 loop_process_work+0xe30/0x1ec0 drivers/block/loop.c:1958
 loop_rootcg_workfn+0x2b/0x40 drivers/block/loop.c:1989
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3346
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3427
 kthread+0xd5c/0xf00 kernel/kthread.c:463
 ret_from_fork+0x1f5/0x4c0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was created at:
 slab_free_hook mm/slub.c:2456 [inline]
 slab_free mm/slub.c:6619 [inline]
 kfree+0x254/0x1460 mm/slub.c:6826
 vfree+0x73c/0xa20 mm/vmalloc.c:3446
 __do_replace+0x1046/0x1120 net/ipv6/netfilter/ip6_tables.c:1107
 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline]
 do_ip6t_set_ctl+0x18f3/0x1da0 net/ipv6/netfilter/ip6_tables.c:1644
 nf_setsockopt+0x4fb/0x550 net/netfilter/nf_sockopt.c:101
 ipv6_setsockopt+0x1c3/0x300 net/ipv6/ipv6_sockglue.c:978
 tcp_setsockopt+0x157/0x180 net/ipv4/tcp.c:4142
 sock_common_setsockopt+0xf5/0x140 net/core/sock.c:3912
 do_sock_setsockopt net/socket.c:2360 [inline]
 __sys_setsockopt+0x43e/0x580 net/socket.c:2385
 __do_sys_setsockopt net/socket.c:2391 [inline]
 __se_sys_setsockopt net/socket.c:2388 [inline]
 __x64_sys_setsockopt+0xf4/0x1a0 net/socket.c:2388
 x64_sys_call+0x27c9/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:55
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Bytes 2044-2047 of 4096 are uninitialized
Memory access of size 4096 starts at ffff8880517b5000
Data copied to user address 00007f123bbc7000

CPU: 0 UID: 0 PID: 6075 Comm: udevd Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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