================================================================== BUG: KCSAN: data-race in vfs_readlink / vfs_unlink write to 0xffff88812523d240 of 4 bytes by task 29012 on cpu 0: dont_mount include/linux/dcache.h:352 [inline] vfs_unlink+0x26a/0x3e0 fs/namei.c:4005 do_unlinkat+0x32b/0x530 fs/namei.c:4067 __do_sys_unlink fs/namei.c:4114 [inline] __se_sys_unlink fs/namei.c:4112 [inline] __x64_sys_unlink+0x3b/0x50 fs/namei.c:4112 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff88812523d240 of 4 bytes by task 3989 on cpu 1: d_is_symlink include/linux/dcache.h:419 [inline] vfs_readlink+0x1bf/0x270 fs/namei.c:4730 do_readlinkat+0x1f1/0x220 fs/stat.c:411 __do_sys_readlink fs/stat.c:432 [inline] __se_sys_readlink fs/stat.c:429 [inline] __x64_sys_readlink+0x51/0x70 fs/stat.c:429 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 3989 Comm: udevd Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 3989 Comm: udevd Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x11d/0x181 lib/dump_stack.c:118 panic+0x210/0x640 kernel/panic.c:221 kcsan_report.cold+0xc/0xd kernel/kcsan/report.c:313 kcsan_setup_watchpoint+0x3fe/0x460 kernel/kcsan/core.c:416 check_access kernel/kcsan/core.c:459 [inline] __tsan_read4+0xc6/0x100 kernel/kcsan/core.c:588 d_is_symlink include/linux/dcache.h:419 [inline] vfs_readlink+0x1bf/0x270 fs/namei.c:4730 do_readlinkat+0x1f1/0x220 fs/stat.c:411 __do_sys_readlink fs/stat.c:432 [inline] __se_sys_readlink fs/stat.c:429 [inline] __x64_sys_readlink+0x51/0x70 fs/stat.c:429 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f03930d8577 Code: f0 ff ff 77 02 f3 c3 48 8b 15 bd 38 2b 00 f7 d8 64 89 02 83 c8 ff c3 90 90 90 90 90 90 90 90 90 90 90 90 b8 59 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 38 2b 00 31 d2 48 29 c2 64 RSP: 002b:00007ffdc7210858 EFLAGS: 00000202 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 0000000000868250 RCX: 00007f03930d8577 RDX: 00000000000003fc RSI: 00007ffdc7210c84 RDI: 00007ffdc7210880 RBP: 00000000000003fc R08: 00000000008680d0 R09: 00007f039312d1d0 R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000dc58 R13: 0000000000000000 R14: 0000000000fb5660 R15: 0000000000868250 Kernel Offset: disabled Rebooting in 86400 seconds..