do_splice_direct_actor fs/splice.c:1201 [inline] do_splice_direct+0xda/0x150 fs/splice.c:1227 do_sendfile+0x380/0x650 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64 fs/read_write.c:1417 [inline] __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1417 x64_sys_call+0x2bb0/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:41 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 ================================================================== BUG: KCSAN: data-race in data_push_tail / vsnprintf write to 0xffffffff88e4f5d0 of 43 bytes by task 14176 on cpu 0: vsnprintf+0x2ce/0x890 lib/vsprintf.c:2878 vscnprintf+0x41/0x90 lib/vsprintf.c:2991 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2216 vprintk_store+0x599/0x860 kernel/printk/printk.c:2336 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2475 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x24d/0x280 lib/fault-inject.c:174 should_failslab+0x8c/0xb0 mm/failslab.c:46 slab_pre_alloc_hook mm/slub.c:4133 [inline] slab_alloc_node mm/slub.c:4209 [inline] __kmalloc_cache_noprof+0x4c/0x320 mm/slub.c:4391 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] nl80211_dump_wiphy+0x8a/0x470 net/wireless/nl80211.c:3235 genl_dumpit+0xac/0x110 net/netlink/genetlink.c:1027 netlink_dump+0x452/0x8a0 net/netlink/af_netlink.c:2327 __netlink_dump_start+0x43e/0x520 net/netlink/af_netlink.c:2442 genl_family_rcv_msg_dumpit+0x115/0x180 net/netlink/genetlink.c:1076 genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline] genl_rcv_msg+0x3f0/0x460 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5bd/0x690 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x58b/0x6b0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x142/0x180 net/socket.c:729 ____sys_sendmsg+0x31e/0x4e0 net/socket.c:2614 ___sys_sendmsg+0x17b/0x1d0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2703 x64_sys_call+0x191e/0x2ff0 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 read to 0xffffffff88e4f5e0 of 8 bytes by task 14175 on cpu 1: data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline] data_push_tail+0xfd/0x420 kernel/printk/printk_ringbuffer.c:679 data_alloc+0xbf/0x2b0 kernel/printk/printk_ringbuffer.c:1054 prb_reserve+0x808/0xaf0 kernel/printk/printk_ringbuffer.c:1669 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2475 printk_stack_address arch/x86/kernel/dumpstack.c:70 [inline] show_trace_log_lvl+0x4e3/0x560 arch/x86/kernel/dumpstack.c:282 __dump_stack+0x1d/0x30 lib/dump_stack.c:94 dump_stack_lvl+0xe8/0x140 lib/dump_stack.c:120 dump_stack+0x15/0x1b lib/dump_stack.c:129 fail_dump lib/fault-inject.c:73 [inline] should_fail_ex+0x265/0x280 lib/fault-inject.c:174 should_failslab+0x8c/0xb0 mm/failslab.c:46 slab_pre_alloc_hook mm/slub.c:4133 [inline] slab_alloc_node mm/slub.c:4209 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_node_track_caller_noprof+0xa4/0x410 mm/slub.c:4384 __kmemdup_nul mm/util.c:64 [inline] kstrndup+0x80/0x130 mm/util.c:120 resume_store+0xf2/0x3d0 kernel/power/hibernate.c:1291 kobj_attr_store+0x4a/0x70 lib/kobject.c:840 sysfs_kf_write+0xfb/0x120 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x1be/0x2d0 fs/kernfs/file.c:334 iter_file_splice_write+0x669/0x9e0 fs/splice.c:738 do_splice_from fs/splice.c:935 [inline] direct_splice_actor+0x156/0x2a0 fs/splice.c:1158 splice_direct_to_actor+0x312/0x680 fs/splice.c:1102 do_splice_direct_actor fs/splice.c:1201 [inline] do_splice_direct+0xda/0x150 fs/splice.c:1227 do_sendfile+0x380/0x650 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64 fs/read_write.c:1417 [inline] __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1417 x64_sys_call+0x2bb0/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:41 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: 0x00000000fffff784 -> 0x676e6963726f6620 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 14175 Comm: syz.7.3604 Tainted: G W 6.17.0-rc1-syzkaller-00211-g90d970cade8e #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 ================================================================== RIP: 0033:0x7faa5bc2ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007faa5a68f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007faa5be55fa0 RCX: 00007faa5bc2ebe9 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000007 RBP: 00007faa5a68f090 R08: 0000000000000000 R09: 0000000000000000 R10: 00008000fffffffe R11: 0000000000000246 R12: 0000000000000001 R13: 00007faa5be56038 R14: 00007faa5be55fa0 R15: 00007ffe542f5c48