================================================================== BUG: KCSAN: data-race in copy_page_to_iter / ext4_setup_super read-write to 0xffff8881411d043a of 2 bytes by task 16114 on cpu 0: ext4_setup_super+0x237/0x5c0 fs/ext4/super.c:3153 __ext4_fill_super fs/ext4/super.c:5346 [inline] ext4_fill_super+0x432a/0x4eb0 fs/ext4/super.c:5603 get_tree_bdev+0x2b4/0x3b0 fs/super.c:1292 ext4_get_tree+0x18/0x20 fs/ext4/super.c:5633 vfs_get_tree+0x49/0x190 fs/super.c:1497 do_new_mount+0x200/0x650 fs/namespace.c:3040 path_mount+0x4b1/0xb60 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount+0x281/0x2d0 fs/namespace.c:3568 __x64_sys_mount+0x63/0x70 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881411d0400 of 1024 bytes by task 12699 on cpu 1: instrument_copy_to_user include/linux/instrumented.h:119 [inline] copyout lib/iov_iter.c:154 [inline] copy_page_to_iter_iovec lib/iov_iter.c:226 [inline] __copy_page_to_iter lib/iov_iter.c:852 [inline] copy_page_to_iter+0x415/0x7b0 lib/iov_iter.c:880 copy_folio_to_iter include/linux/uio.h:153 [inline] filemap_read+0x10b2/0x1400 mm/filemap.c:2730 blkdev_read_iter+0x2c6/0x370 block/fops.c:611 call_read_iter include/linux/fs.h:2044 [inline] new_sync_read fs/read_write.c:401 [inline] vfs_read+0x5a5/0x6a0 fs/read_write.c:482 ksys_read+0xe8/0x1a0 fs/read_write.c:620 __do_sys_read fs/read_write.c:630 [inline] __se_sys_read fs/read_write.c:628 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:628 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 12699 Comm: udevd Not tainted 5.18.0-rc6-syzkaller-00009-gfeb9c5e19e91 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================