Hello, syzbot found the following issue on: HEAD commit: da3ea35007d0 Linux 6.11-rc7 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=172d743b980000 kernel config: https://syzkaller.appspot.com/x/.config?x=1e7d02549be622b2 dashboard link: https://syzkaller.appspot.com/bug?extid=a388a53633c9a4e9b22e compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/3cf4ae8a1204/disk-da3ea350.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d8186bac98f7/vmlinux-da3ea350.xz kernel image: https://storage.googleapis.com/syzbot-assets/a1ab98f32196/bzImage-da3ea350.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a388a53633c9a4e9b22e@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KCSAN: data-race in redirty_tail_locked / vfs_fsync_range read-write to 0xffff88811317dce8 of 8 bytes by task 4275 on cpu 0: redirty_tail_locked+0x56/0x270 fs/fs-writeback.c:1346 writeback_single_inode+0x1ea/0x4a0 fs/fs-writeback.c:1792 sync_inode_metadata+0x5c/0x90 fs/fs-writeback.c:2842 generic_buffers_fsync_noflush+0xe4/0x130 fs/buffer.c:610 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline] ext4_sync_file+0x20b/0x6c0 fs/ext4/fsync.c:151 vfs_fsync_range+0x122/0x140 fs/sync.c:188 generic_write_sync include/linux/fs.h:2822 [inline] ext4_buffered_write_iter+0x338/0x380 fs/ext4/file.c:305 ext4_file_write_iter+0x29f/0xe30 iter_file_splice_write+0x5e6/0x970 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x16c/0x2c0 fs/splice.c:1164 splice_direct_to_actor+0x305/0x670 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0xd7/0x150 fs/splice.c:1233 do_sendfile+0x3ab/0x950 fs/read_write.c:1295 __do_sys_sendfile64 fs/read_write.c:1362 [inline] __se_sys_sendfile64 fs/read_write.c:1348 [inline] __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348 x64_sys_call+0xed5/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:41 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff88811317dce8 of 8 bytes by task 4277 on cpu 1: vfs_fsync_range+0xa6/0x140 fs/sync.c:186 generic_write_sync include/linux/fs.h:2822 [inline] ext4_buffered_write_iter+0x338/0x380 fs/ext4/file.c:305 ext4_file_write_iter+0x29f/0xe30 iter_file_splice_write+0x5e6/0x970 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x16c/0x2c0 fs/splice.c:1164 splice_direct_to_actor+0x305/0x670 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0xd7/0x150 fs/splice.c:1233 do_sendfile+0x3ab/0x950 fs/read_write.c:1295 __do_sys_sendfile64 fs/read_write.c:1362 [inline] __se_sys_sendfile64 fs/read_write.c:1348 [inline] __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348 x64_sys_call+0xed5/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:41 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x0000000000000087 -> 0x0000000000000080 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 4277 Comm: syz.2.232 Not tainted 6.11.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
