================================================================== BUG: KCSAN: data-race in ext4_mb_find_by_goal / mb_free_blocks write to 0xffff8881004773d4 of 4 bytes by task 14260 on cpu 1: mb_free_blocks+0x156/0xb40 fs/ext4/mballoc.c:1798 ext4_free_blocks+0x1418/0x1b50 fs/ext4/mballoc.c:5988 ext4_remove_blocks+0x61a/0x800 fs/ext4/extents.c:2502 ext4_ext_rm_leaf+0x670/0xd20 fs/ext4/extents.c:2668 ext4_ext_remove_space+0x901/0x1300 fs/ext4/extents.c:2916 ext4_ext_truncate+0xfe/0x170 fs/ext4/extents.c:4377 ext4_truncate+0x76e/0xa80 fs/ext4/inode.c:4262 ext4_setattr+0xacc/0xec0 fs/ext4/inode.c:5504 notify_change+0x8a3/0xa80 fs/attr.c:398 do_truncate+0xe8/0x130 fs/open.c:64 handle_truncate fs/namei.c:3017 [inline] do_open fs/namei.c:3365 [inline] path_openat+0x1a79/0x20b0 fs/namei.c:3494 do_filp_open+0xd9/0x1f0 fs/namei.c:3521 do_sys_openat2+0xa3/0x250 fs/open.c:1195 do_sys_open fs/open.c:1211 [inline] __do_sys_creat fs/open.c:1285 [inline] __se_sys_creat fs/open.c:1279 [inline] __x64_sys_creat+0x62/0x80 fs/open.c:1279 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881004773d4 of 4 bytes by task 14263 on cpu 0: ext4_mb_find_by_goal+0x129/0x890 fs/ext4/mballoc.c:2202 ext4_mb_regular_allocator+0x11c/0x2520 fs/ext4/mballoc.c:2635 ext4_mb_new_blocks+0x762/0x1f90 fs/ext4/mballoc.c:5514 ext4_ext_map_blocks+0x1569/0x1f00 fs/ext4/extents.c:4245 ext4_map_blocks+0x70d/0xef0 fs/ext4/inode.c:638 ext4_alloc_file_blocks+0x271/0x720 fs/ext4/extents.c:4432 ext4_fallocate+0x2a7/0x4d0 fs/ext4/extents.c:4712 vfs_fallocate+0x463/0x660 fs/open.c:311 file_ioctl fs/ioctl.c:497 [inline] do_vfs_ioctl+0x1322/0x1410 fs/ioctl.c:1048 __do_sys_ioctl fs/ioctl.c:1067 [inline] __se_sys_ioctl+0x83/0x140 fs/ioctl.c:1055 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000800 -> 0x00005800 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 14263 Comm: syz-executor.1 Tainted: G W 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================