syzbot

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BUG: KMSAN: uninit-value in netlink_rcv_skb+0x280/0x650 net/netlink/af_netlink.c:2548
 netlink_rcv_skb+0x280/0x650 net/netlink/af_netlink.c:2548
 rtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6613
 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
 netlink_unicast+0xf4c/0x1260 net/netlink/af_netlink.c:1361
 netlink_sendmsg+0x10df/0x11f0 net/netlink/af_netlink.c:1905
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x30f/0x380 net/socket.c:745
 sock_sendmsg+0xe0/0x190 net/socket.c:768
 splice_to_socket+0x11f5/0x1b70 fs/splice.c:889
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x33d/0x7f0 fs/splice.c:1164
 splice_direct_to_actor+0x94b/0x1430 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x1fd/0x340 fs/splice.c:1233
 do_sendfile+0x9aa/0x1920 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64+0x1f5/0x280 fs/read_write.c:1348
 __x64_sys_sendfile64+0xbd/0x110 fs/read_write.c:1348
 x64_sys_call+0x39e6/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:122 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 _copy_from_iter+0xe06/0x2460 lib/iov_iter.c:260
 copy_from_iter include/linux/uio.h:204 [inline]
 copy_from_iter_full include/linux/uio.h:221 [inline]
 memcpy_from_msg include/linux/skbuff.h:4128 [inline]
 netlink_sendmsg+0xc29/0x11f0 net/netlink/af_netlink.c:1890
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x30f/0x380 net/socket.c:745
 sock_sendmsg+0xe0/0x190 net/socket.c:768
 splice_to_socket+0x11f5/0x1b70 fs/splice.c:889
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x33d/0x7f0 fs/splice.c:1164
 splice_direct_to_actor+0x94b/0x1430 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x1fd/0x340 fs/splice.c:1233
 do_sendfile+0x9aa/0x1920 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64+0x1f5/0x280 fs/read_write.c:1348
 __x64_sys_sendfile64+0xbd/0x110 fs/read_write.c:1348
 x64_sys_call+0x39e6/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 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:122 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0xe45/0x24b0 lib/iov_iter.c:185
 copy_page_to_iter+0x419/0x880 lib/iov_iter.c:362
 shmem_file_read_iter+0xa0a/0x12b0 mm/shmem.c:2866
 do_iter_readv_writev+0x7e6/0x960
 vfs_iter_read+0x279/0x700 fs/read_write.c:830
 lo_read_simple drivers/block/loop.c:286 [inline]
 do_req_filebacked drivers/block/loop.c:496 [inline]
 loop_handle_cmd drivers/block/loop.c:1907 [inline]
 loop_process_work+0x2053/0x3440 drivers/block/loop.c:1942
 loop_workfn+0x48/0x60 drivers/block/loop.c:1966
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0xa81/0x1bd0 kernel/workqueue.c:3348
 worker_thread+0xea5/0x1560 kernel/workqueue.c:3429
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:122 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_page_from_iter_atomic+0x12b7/0x2ae0 lib/iov_iter.c:481
 generic_perform_write+0x4c1/0xc60 mm/filemap.c:3982
 shmem_file_write_iter+0x2bd/0x2f0 mm/shmem.c:2920
 do_iter_readv_writev+0x7e6/0x960
 vfs_iter_write+0x459/0xd00 fs/read_write.c:895
 lo_write_bvec drivers/block/loop.c:246 [inline]
 lo_write_simple drivers/block/loop.c:267 [inline]
 do_req_filebacked drivers/block/loop.c:491 [inline]
 loop_handle_cmd drivers/block/loop.c:1907 [inline]
 loop_process_work+0x1502/0x3440 drivers/block/loop.c:1942
 loop_rootcg_workfn+0x2b/0x40 drivers/block/loop.c:1973
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0xa81/0x1bd0 kernel/workqueue.c:3348
 worker_thread+0xea5/0x1560 kernel/workqueue.c:3429
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:122 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_page_from_iter_atomic+0x12b7/0x2ae0 lib/iov_iter.c:481
 generic_perform_write+0x4c1/0xc60 mm/filemap.c:3982
 ext4_buffered_write_iter+0x564/0xaa0 fs/ext4/file.c:299
 ext4_file_write_iter+0x208/0x3450
 __kernel_write_iter+0x64d/0xc80 fs/read_write.c:523
 dump_emit_page fs/coredump.c:895 [inline]
 dump_user_range+0x8dc/0xee0 fs/coredump.c:956
 elf_core_dump+0x57c7/0x5ae0 fs/binfmt_elf.c:2083
 do_coredump+0x32d5/0x4920 fs/coredump.c:769
 get_signal+0x267e/0x2d00 kernel/signal.c:2896
 arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x5d/0x160 kernel/entry/common.c:218
 do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 __alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
 alloc_pages_mpol+0x299/0x990 mm/mempolicy.c:2264
 alloc_pages+0x1bf/0x1e0 mm/mempolicy.c:2335
 dump_user_range+0x4a/0xee0 fs/coredump.c:940
 elf_core_dump+0x57c7/0x5ae0 fs/binfmt_elf.c:2083
 do_coredump+0x32d5/0x4920 fs/coredump.c:769
 get_signal+0x267e/0x2d00 kernel/signal.c:2896
 arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x5d/0x160 kernel/entry/common.c:218
 do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 PID: 6747 Comm: syz-executor.1 Tainted: G        W          6.9.0-syzkaller-02707-g614da38e2f7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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