================================================================== BUG: KCSAN: data-race in data_push_tail / vsnprintf write to 0xffffffff86ea2fd1 of 1 bytes by task 7973 on cpu 0: vsnprintf+0xdd0/0xe20 vscnprintf+0x42/0x80 lib/vsprintf.c:2924 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2128 vprintk_store+0x56f/0x800 kernel/printk/printk.c:2242 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2288 vprintk_default+0x26/0x30 kernel/printk/printk.c:2322 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2332 show_ip arch/x86/kernel/dumpstack.c:142 [inline] show_iret_regs+0x2e/0x60 arch/x86/kernel/dumpstack.c:149 __show_regs+0x2b/0x430 arch/x86/kernel/process_64.c:75 show_trace_log_lvl+0x3d2/0x510 arch/x86/kernel/dumpstack.c:301 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xda/0x130 lib/dump_stack.c:106 dump_stack+0x15/0x20 lib/dump_stack.c:113 fail_dump lib/fault-inject.c:52 [inline] should_fail_ex+0x21f/0x230 lib/fault-inject.c:153 __should_failslab+0x92/0xa0 mm/failslab.c:44 should_failslab+0x9/0x20 mm/slab_common.c:1512 slab_pre_alloc_hook+0x38/0x180 mm/slab.h:711 slab_alloc_node mm/slub.c:3460 [inline] kmem_cache_alloc_node+0x54/0x240 mm/slub.c:3523 __alloc_skb+0x109/0x2e0 net/core/skbuff.c:640 alloc_skb include/linux/skbuff.h:1286 [inline] nlmsg_new include/net/netlink.h:999 [inline] netlink_ack+0x241/0x950 net/netlink/af_netlink.c:2482 netlink_rcv_skb+0x18f/0x220 net/netlink/af_netlink.c:2551 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1075 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x589/0x650 net/netlink/af_netlink.c:1368 netlink_sendmsg+0x66e/0x770 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x37c/0x4d0 net/socket.c:2558 ___sys_sendmsg net/socket.c:2612 [inline] __sys_sendmsg+0x1e9/0x270 net/socket.c:2641 __do_sys_sendmsg net/socket.c:2650 [inline] __se_sys_sendmsg net/socket.c:2648 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2648 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffffffff86ea2fd0 of 8 bytes by task 7958 on cpu 1: data_make_reusable kernel/printk/printk_ringbuffer.c:590 [inline] data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:675 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1046 prb_reserve+0x893/0xbc0 kernel/printk/printk_ringbuffer.c:1555 vprintk_store+0x53e/0x800 kernel/printk/printk.c:2232 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2288 vprintk_default+0x26/0x30 kernel/printk/printk.c:2322 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2332 __quota_error+0xf3/0x100 fs/quota/dquot.c:149 write_blk fs/quota/quota_tree.c:67 [inline] get_free_dqblk+0x210/0x2d0 fs/quota/quota_tree.c:130 do_insert_tree+0x14c/0xde0 fs/quota/quota_tree.c:340 do_insert_tree+0x4ab/0xde0 fs/quota/quota_tree.c:375 do_insert_tree+0x4ab/0xde0 fs/quota/quota_tree.c:375 do_insert_tree+0x4ab/0xde0 fs/quota/quota_tree.c:375 dq_insert_tree fs/quota/quota_tree.c:401 [inline] qtree_write_dquot+0x241/0x2b0 fs/quota/quota_tree.c:420 v2_write_dquot+0x9e/0xd0 fs/quota/quota_v2.c:358 dquot_acquire+0x1c8/0x2d0 fs/quota/dquot.c:470 ext4_acquire_dquot+0x161/0x1a0 fs/ext4/super.c:6868 dqget+0x51c/0x880 fs/quota/dquot.c:984 __dquot_initialize+0x18a/0x750 fs/quota/dquot.c:1510 dquot_initialize+0x1a/0x20 fs/quota/dquot.c:1568 ext4_process_orphan+0x32/0x1c0 fs/ext4/orphan.c:329 ext4_orphan_cleanup+0x669/0x9b0 fs/ext4/orphan.c:474 __ext4_fill_super fs/ext4/super.c:5582 [inline] ext4_fill_super+0x35fa/0x3940 fs/ext4/super.c:5703 get_tree_bdev+0x272/0x300 fs/super.c:1577 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5735 vfs_get_tree+0x51/0x1b0 fs/super.c:1750 do_new_mount+0x203/0x660 fs/namespace.c:3335 path_mount+0x496/0xb30 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x0000000100001819 -> 0x000000010000000a Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7958 Comm: syz-executor.1 Not tainted 6.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 ================================================================== EXT4-fs (loop1): 1 orphan inode deleted EXT4-fs (loop1): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback. ext4 filesystem being mounted at /root/syzkaller-testdir1728340128/syzkaller.ao6cfx/3222/file1 supports timestamps until 2038-01-19 (0x7fffffff) syz-executor.1 (7958) used greatest stack depth: 9064 bytes left