EXT4-fs (loop1): ext4_check_descriptors: Inode bitmap for group 0 overlaps block group descriptors
EXT4-fs (loop1): ext4_check_descriptors: Checksum for group 0 failed (24509!=33349)
EXT4-fs (loop1): failed to initialize system zone (-117)
EXT4-fs (loop1): mount failed
==================================================================
BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237d264e8 of 1 bytes by task 6504 on cpu 1:
 folio_batch_add include/linux/pagevec.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:194 [inline]
 folio_add_lru+0xa4/0x1e0 mm/swap.c:511
 shmem_alloc_and_add_folio mm/shmem.c:2020 [inline]
 shmem_get_folio_gfp+0x7b0/0xd60 mm/shmem.c:2585
 shmem_get_folio mm/shmem.c:2691 [inline]
 shmem_write_begin+0xfc/0x1f0 mm/shmem.c:3344
 generic_perform_write+0x183/0x490 mm/filemap.c:4314
 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3519
 __kernel_write_iter+0x319/0x590 fs/read_write.c:621
 dump_emit_page fs/coredump.c:1299 [inline]
 dump_user_range+0xa7d/0xdb0 fs/coredump.c:1373
 elf_core_dump+0x21a2/0x2330 fs/binfmt_elf.c:2111
 coredump_write+0xacf/0xdf0 fs/coredump.c:1050
 do_coredump fs/coredump.c:1127 [inline]
 vfs_coredump+0x26c7/0x3130 fs/coredump.c:1201
 get_signal+0xd7b/0xf60 kernel/signal.c:3019
 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:98 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
 irqentry_exit+0xf7/0x520 kernel/entry/common.c:219
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618

read to 0xffff888237d264e8 of 1 bytes by task 6573 on cpu 0:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:780 [inline]
 __lru_add_drain_all+0x17e/0x450 mm/swap.c:877
 lru_add_drain_all+0x10/0x20 mm/swap.c:893
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 __ext4_fill_super fs/ext4/super.c:5757 [inline]
 ext4_fill_super+0x2d52/0x3800 fs/ext4/super.c:5782
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1694
 get_tree_bdev+0x1f/0x30 fs/super.c:1717
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5814
 vfs_get_tree+0x57/0x1d0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3760 [inline]
 do_new_mount+0x288/0x8d0 fs/namespace.c:3836
 path_mount+0x4d0/0xbc0 fs/namespace.c:4146
 do_mount fs/namespace.c:4159 [inline]
 __do_sys_mount fs/namespace.c:4348 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4325
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4325
 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x12 -> 0x14

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6573 Comm: syz.1.499 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
==================================================================