netlink: 24 bytes leftover after parsing attributes in process `syz.2.4794'.
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BUG: KCSAN: data-race in data_alloc / data_push_tail

write to 0xffffffff88404c90 of 8 bytes by task 19835 on cpu 1:
 data_alloc+0x216/0x2c0 kernel/printk/printk_ringbuffer.c:1082
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2266
 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2326
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2360
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2370
 scsi_ioctl+0x452/0x1540 drivers/scsi/scsi_ioctl.c:878
 sg_ioctl_common drivers/scsi/sg.c:1109 [inline]
 sg_ioctl+0xdaa/0x1870 drivers/scsi/sg.c:1163
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xd3/0x150 fs/ioctl.c:893
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:893
 x64_sys_call+0x1581/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff88404c90 of 8 bytes by task 19833 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:679
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1054
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2266
 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2326
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2360
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2370
 __nla_validate_parse+0x1881/0x1e30 lib/nlattr.c:647
 __nla_parse+0x40/0x60 lib/nlattr.c:732
 __nlmsg_parse include/net/netlink.h:761 [inline]
 nlmsg_parse_deprecated include/net/netlink.h:802 [inline]
 rtnl_calcit net/core/rtnetlink.c:3985 [inline]
 rtnetlink_rcv_msg+0x65a/0x910 net/core/rtnetlink.c:6574
 netlink_rcv_skb+0x12c/0x230 net/netlink/af_netlink.c:2564
 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6653
 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
 netlink_unicast+0x58d/0x660 net/netlink/af_netlink.c:1361
 netlink_sendmsg+0x5ca/0x6e0 net/netlink/af_netlink.c:1905
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x140/0x180 net/socket.c:745
 ____sys_sendmsg+0x312/0x410 net/socket.c:2585
 ___sys_sendmsg net/socket.c:2639 [inline]
 __sys_sendmsg+0x1e9/0x280 net/socket.c:2668
 __do_sys_sendmsg net/socket.c:2677 [inline]
 __se_sys_sendmsg net/socket.c:2675 [inline]
 __x64_sys_sendmsg+0x46/0x50 net/socket.c:2675
 x64_sys_call+0xb25/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000100000287 -> 0x0000000100000dfd

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 19833 Comm: syz.2.4794 Not tainted 6.10.0-rc5-syzkaller-00243-g6c0483dbfe72 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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