netlink: 12 bytes leftover after parsing attributes in process `syz.1.19102'. netlink: 'syz.1.19102': attribute type 4 has an invalid length. ================================================================== BUG: KCSAN: data-race in data_alloc / prb_reserve write to 0xffffffff86895918 of 8 bytes by task 29786 on cpu 1: data_alloc+0x280/0x2e0 kernel/printk/printk_ringbuffer.c:1102 prb_reserve+0x807/0xaf0 kernel/printk/printk_ringbuffer.c:1685 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2299 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2448 __ext4_std_error+0x346/0x370 fs/ext4/super.c:965 ext4_free_inode+0x79e/0x870 fs/ext4/ialloc.c:361 ext4_evict_inode+0xb0c/0xd90 fs/ext4/inode.c:306 evict+0x2e3/0x550 fs/inode.c:810 iput_final fs/inode.c:1914 [inline] iput+0x4ed/0x650 fs/inode.c:1966 ext4_process_orphan+0x1a9/0x1c0 fs/ext4/orphan.c:356 ext4_orphan_cleanup+0x6a8/0xa00 fs/ext4/orphan.c:470 __ext4_fill_super fs/ext4/super.c:5617 [inline] ext4_fill_super+0x3483/0x3810 fs/ext4/super.c:5736 get_tree_bdev_flags+0x291/0x300 fs/super.c:1691 get_tree_bdev+0x1f/0x30 fs/super.c:1714 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5768 vfs_get_tree+0x57/0x1d0 fs/super.c:1751 fc_mount fs/namespace.c:1208 [inline] do_new_mount_fc fs/namespace.c:3651 [inline] do_new_mount+0x24d/0x660 fs/namespace.c:3727 path_mount+0x4a5/0xb70 fs/namespace.c:4037 do_mount fs/namespace.c:4050 [inline] __do_sys_mount fs/namespace.c:4238 [inline] __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4215 __x64_sys_mount+0x67/0x80 fs/namespace.c:4215 x64_sys_call+0x2b51/0x3000 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff86895918 of 8 bytes by task 29793 on cpu 0: desc_read kernel/printk/printk_ringbuffer.c:479 [inline] desc_push_tail kernel/printk/printk_ringbuffer.c:775 [inline] desc_reserve kernel/printk/printk_ringbuffer.c:921 [inline] prb_reserve+0x220/0xaf0 kernel/printk/printk_ringbuffer.c:1635 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2299 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2448 __nla_validate_parse+0x1738/0x1d00 lib/nlattr.c:647 __nla_parse+0x40/0x60 lib/nlattr.c:732 __nlmsg_parse include/net/netlink.h:789 [inline] nlmsg_parse_deprecated include/net/netlink.h:830 [inline] rtnl_newlink+0xf1/0x12d0 net/core/rtnetlink.c:3970 rtnetlink_rcv_msg+0x5fe/0x6d0 net/core/rtnetlink.c:6954 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2552 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6981 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5c0/0x690 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x58b/0x6b0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x145/0x180 net/socket.c:742 ____sys_sendmsg+0x31e/0x4e0 net/socket.c:2630 ___sys_sendmsg+0x17b/0x1d0 net/socket.c:2684 __sys_sendmsg net/socket.c:2716 [inline] __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2719 x64_sys_call+0x191e/0x3000 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000000001baad8 -> 0x000000000025b058 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 29793 Comm: syz.1.19102 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 ================================================================== netlink: 152 bytes leftover after parsing attributes in process `syz.1.19102'.