lsm_file_alloc security/security.c:733 [inline] security_file_alloc+0x32/0x100 security/security.c:2888 init_file+0x5c/0x1d0 fs/file_table.c:159 alloc_empty_file+0x8b/0x200 fs/file_table.c:241 path_openat+0x68/0x2170 fs/namei.c:4032 ================================================================== BUG: KCSAN: data-race in _prb_read_valid / data_alloc write to 0xffffffff8688f690 of 8 bytes by task 6583 on cpu 0: data_alloc+0x271/0x2b0 kernel/printk/printk_ringbuffer.c:1095 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 set_capacity_and_notify+0x14c/0x1f0 block/genhd.c:93 loop_set_size+0x2e/0x70 drivers/block/loop.c:210 loop_configure+0x8d3/0xa50 drivers/block/loop.c:1067 lo_ioctl+0x1e1/0x1350 drivers/block/loop.c:1523 blkdev_ioctl+0x34f/0x440 block/ioctl.c:705 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl+0xce/0x140 fs/ioctl.c:584 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:584 x64_sys_call+0x1816/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:17 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 0xffffffff8688f690 of 16 bytes by task 6593 on cpu 1: desc_read kernel/printk/printk_ringbuffer.c:482 [inline] desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1874 [inline] prb_read kernel/printk/printk_ringbuffer.c:1922 [inline] _prb_read_valid+0x1bc/0x920 kernel/printk/printk_ringbuffer.c:2113 desc_update_last_finalized kernel/printk/printk_ringbuffer.c:1515 [inline] prb_final_commit+0x136/0x1e0 kernel/printk/printk_ringbuffer.c:1782 vprintk_store+0x741/0x860 kernel/printk/printk.c:2352 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] kmem_cache_alloc_noprof+0x50/0x310 mm/slub.c:4236 lsm_file_alloc security/security.c:733 [inline] security_file_alloc+0x32/0x100 security/security.c:2888 init_file+0x5c/0x1d0 fs/file_table.c:159 alloc_empty_file+0x8b/0x200 fs/file_table.c:241 path_openat+0x68/0x2170 fs/namei.c:4032 do_filp_open+0x109/0x230 fs/namei.c:4073 do_open_execat+0xd8/0x260 fs/exec.c:783 open_exec+0x3d/0x60 fs/exec.c:822 bm_register_write+0x8e9/0xbf0 fs/binfmt_misc.c:795 vfs_write+0x269/0x8e0 fs/read_write.c:684 ksys_write+0xda/0x1a0 fs/read_write.c:738 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x40/0x50 fs/read_write.c:746 x64_sys_call+0x27fe/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:2 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 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 6593 Comm: syz.0.14341 Tainted: G W 6.16.0-syzkaller-11743-g6bcdbd62bd56 #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 ================================================================== do_filp_open+0x109/0x230 fs/namei.c:4073 do_open_execat+0xd8/0x260 fs/exec.c:783 open_exec+0x3d/0x60 fs/exec.c:822 bm_register_write+0x8e9/0xbf0 fs/binfmt_misc.c:795 vfs_write+0x269/0x8e0 fs/read_write.c:684 ksys_write+0xda/0x1a0 fs/read_write.c:738 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x40/0x50 fs/read_write.c:746 x64_sys_call+0x27fe/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:2 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 RIP: 0033:0x7f24964febe9 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:00007f2494b67038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f2496725fa0 RCX: 00007f24964febe9 RDX: 0000000000000032 RSI: 0000200000000440 RDI: 0000000000000004 RBP: 00007f2494b67090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f2496726038 R14: 00007f2496725fa0 R15: 00007ffd7508e8c8 binfmt_misc: register: failed to install interpreter file ./file2