FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 ================================================================== BUG: KCSAN: data-race in data_push_tail / uuid_string write to 0xffffffff893b00a8 of 1 bytes by task 9966 on cpu 1: string_nocheck lib/vsprintf.c:652 [inline] uuid_string+0x3ca/0x450 lib/vsprintf.c:1774 pointer+0x3e2/0xc90 lib/vsprintf.c:2571 vsnprintf+0x49e/0x8c0 lib/vsprintf.c:2949 va_format lib/vsprintf.c:1725 [inline] pointer+0x844/0xc90 lib/vsprintf.c:2573 vsnprintf+0x49e/0x8c0 lib/vsprintf.c:2949 vscnprintf+0x41/0x90 lib/vsprintf.c:3014 printk_sprint+0x30/0x2b0 kernel/printk/printk.c:2222 vprintk_store+0x57b/0x910 kernel/printk/printk.c:2364 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2504 __ext4_msg+0x1aa/0x1c0 fs/ext4/super.c:1001 ext4_fill_super+0x2f20/0x3760 fs/ext4/super.c:5843 get_tree_bdev_flags+0x291/0x300 fs/super.c:1634 get_tree_bdev+0x1f/0x30 fs/super.c:1657 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5860 vfs_get_tree+0x57/0x1d0 fs/super.c:1694 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3765 [inline] do_new_mount+0x288/0x8d0 fs/namespace.c:3841 path_mount+0x4ad/0xb90 fs/namespace.c:4161 do_mount fs/namespace.c:4174 [inline] __do_sys_mount fs/namespace.c:4390 [inline] __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4367 __x64_sys_mount+0x67/0x80 fs/namespace.c:4367 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff893b00a8 of 8 bytes by task 9973 on cpu 0: data_make_reusable kernel/printk/printk_ringbuffer.c:608 [inline] data_push_tail+0x104/0x440 kernel/printk/printk_ringbuffer.c:693 data_alloc+0x111/0x380 kernel/printk/printk_ringbuffer.c:1089 prb_reserve+0x8e3/0xaf0 kernel/printk/printk_ringbuffer.c:1727 vprintk_store+0x54a/0x910 kernel/printk/printk.c:2354 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2504 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x246/0x270 lib/fault-inject.c:174 should_failslab+0x8c/0xb0 mm/failslab.c:46 slab_pre_alloc_hook mm/slub.c:4567 [inline] slab_alloc_node mm/slub.c:4925 [inline] kmem_cache_alloc_noprof+0x7f/0x3c0 mm/slub.c:4959 lsm_file_alloc security/security.c:171 [inline] security_file_alloc+0x32/0xf0 security/security.c:2406 init_file+0x5b/0x1b0 fs/file_table.c:184 alloc_empty_file+0x85/0x1e0 fs/file_table.c:266 alloc_file fs/file_table.c:396 [inline] alloc_file_pseudo+0x92/0x120 fs/file_table.c:427 __shmem_file_setup+0x226/0x260 mm/shmem.c:5804 shmem_file_setup+0x3b/0x50 mm/shmem.c:5836 memfd_alloc_file+0x4e/0x300 mm/memfd.c:471 __do_sys_memfd_create mm/memfd.c:522 [inline] __se_sys_memfd_create+0x2e1/0x3b0 mm/memfd.c:505 __x64_sys_memfd_create+0x31/0x40 mm/memfd.c:505 x64_sys_call+0x1f22/0x3020 arch/x86/include/generated/asm/syscalls_64.h:320 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x3ffffffffffff371 -> 0x30302d303030302d Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 9973 Comm: syz.9.1643 Tainted: G W syzkaller #0 PREEMPT(lazy) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 ================================================================== CPU: 0 UID: 0 PID: 9973 Comm: syz.9.1643 Tainted: G W syzkaller #0 PREEMPT(lazy) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: __dump_stack+0x1d/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x95/0xd0 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+0x25e/0x270 lib/fault-inject.c:174 should_failslab+0x8c/0xb0 mm/failslab.c:46 slab_pre_alloc_hook mm/slub.c:4567 [inline] slab_alloc_node mm/slub.c:4925 [inline] kmem_cache_alloc_noprof+0x7f/0x3c0 mm/slub.c:4959 lsm_file_alloc security/security.c:171 [inline] security_file_alloc+0x32/0xf0 security/security.c:2406 init_file+0x5b/0x1b0 fs/file_table.c:184 alloc_empty_file+0x85/0x1e0 fs/file_table.c:266 alloc_file fs/file_table.c:396 [inline] alloc_file_pseudo+0x92/0x120 fs/file_table.c:427 __shmem_file_setup+0x226/0x260 mm/shmem.c:5804 shmem_file_setup+0x3b/0x50 mm/shmem.c:5836 memfd_alloc_file+0x4e/0x300 mm/memfd.c:471 __do_sys_memfd_create mm/memfd.c:522 [inline] __se_sys_memfd_create+0x2e1/0x3b0 mm/memfd.c:505 __x64_sys_memfd_create+0x31/0x40 mm/memfd.c:505 x64_sys_call+0x1f22/0x3020 arch/x86/include/generated/asm/syscalls_64.h:320 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdbdb0dce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fdbd9b2ee08 EFLAGS: 00000202 ORIG_RAX: 000000000000013f RAX: ffffffffffffffda RBX: 0000000000000516 RCX: 00007fdbdb0dce59 RDX: 00007fdbd9b2eee0 RSI: 0000000000000000 RDI: 00007fdbdb17304f RBP: 0000200000001340 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000202 R12: 0000200000000000 R13: 00007fdbd9b2eee0 R14: 00007fdbd9b2eea0 R15: 0000200000001200