================================================================== BUG: KASAN: use-after-free in dx_insert_block fs/ext4/namei.c:1387 [inline] BUG: KASAN: use-after-free in do_split+0x1a78/0x1f70 fs/ext4/namei.c:2080 Read of size 157024 at addr ffff8881123b1028 by task syz.1.50/696 CPU: 1 PID: 696 Comm: syz.1.50 Not tainted 5.15.185-syzkaller-1080761-g5cf73bface18 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0xf1/0x140 mm/kasan/report.c:444 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x280/0x290 mm/kasan/generic.c:189 memmove+0x2d/0x70 mm/kasan/shadow.c:54 dx_insert_block fs/ext4/namei.c:1387 [inline] do_split+0x1a78/0x1f70 fs/ext4/namei.c:2080 make_indexed_dir+0xe01/0x14a0 fs/ext4/namei.c:2392 ext4_add_entry+0xc24/0xf40 fs/ext4/namei.c:2504 __ext4_link+0x4d7/0x770 fs/ext4/namei.c:3536 ext4_link+0x1de/0x270 fs/ext4/namei.c:3577 vfs_link+0x636/0x7f0 fs/namei.c:4557 do_linkat+0x1e7/0x730 fs/namei.c:4628 __do_sys_link fs/namei.c:4662 [inline] __se_sys_link fs/namei.c:4660 [inline] __x64_sys_link+0x86/0x90 fs/namei.c:4660 x64_sys_call+0x34d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:87 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa8f1130169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa8f0ba2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000056 RAX: ffffffffffffffda RBX: 00007fa8f1348fa0 RCX: 00007fa8f1130169 RDX: 0000000000000000 RSI: 0000400000000bc0 RDI: 0000400000001240 RBP: 00007fa8f11b12a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa8f1348fa0 R15: 00007ffdc2c842b8 The buggy address belongs to the page: page:ffffea000448ec40 refcount:3 mapcount:1 mapping:ffff88810928ac98 index:0x1 pfn:0x1123b1 memcg:ffff888100254500 aops:def_blk_aops ino:700001 flags: 0x400000000032201e(referenced|uptodate|dirty|lru|private|mappedtodisk|unevictable|mlocked|zone=1) raw: 400000000032201e ffff88810025e640 ffffea000448ed08 ffff88810928ac98 raw: 0000000000000001 ffff8881114f0c78 0000000300000000 ffff888100254500 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 408, ts 67155837146, free_ts 55219091854 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5795 __alloc_pages_node include/linux/gfp.h:591 [inline] alloc_pages_node include/linux/gfp.h:605 [inline] alloc_pages include/linux/gfp.h:618 [inline] __page_cache_alloc include/linux/pagemap.h:305 [inline] page_cache_ra_unbounded+0x2b2/0x980 mm/readahead.c:227 do_page_cache_ra mm/readahead.c:280 [inline] force_page_cache_ra+0x3fd/0x460 mm/readahead.c:312 page_cache_sync_ra+0x2ae/0x420 mm/readahead.c:590 page_cache_sync_readahead include/linux/pagemap.h:831 [inline] filemap_get_pages mm/filemap.c:2568 [inline] filemap_read+0x63a/0x1f70 mm/filemap.c:2653 generic_file_read_iter+0xac/0x400 mm/filemap.c:2813 blkdev_read_iter+0x12f/0x160 block/fops.c:563 call_read_iter include/linux/fs.h:2206 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0x68b/0xbe0 fs/read_write.c:485 ksys_read+0x140/0x240 fs/read_write.c:623 __do_sys_read fs/read_write.c:633 [inline] __se_sys_read fs/read_write.c:631 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:631 x64_sys_call+0x96d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:1 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534 free_unref_page+0xa2/0x550 mm/page_alloc.c:3616 free_the_page mm/page_alloc.c:805 [inline] __free_pages+0x6c/0x100 mm/page_alloc.c:5871 __vunmap+0x84d/0x9e0 mm/vmalloc.c:2652 __vfree mm/vmalloc.c:2701 [inline] vfree+0x8b/0xc0 mm/vmalloc.c:2732 kcov_put kernel/kcov.c:417 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:519 __fput+0x20b/0x8b0 fs/file_table.c:311 ____fput+0x15/0x20 fs/file_table.c:339 task_work_run+0x127/0x190 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa76/0x27a0 kernel/exit.c:880 do_group_exit+0x141/0x310 kernel/exit.c:1002 get_signal+0x66a/0x1480 kernel/signal.c:2907 arch_do_signal_or_restart+0xc1/0x10f0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0xa7/0xe0 kernel/entry/common.c:178 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307 Memory state around the buggy address: ffff8881123b7f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881123b7f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881123b8000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881123b8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881123b8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== EXT4-fs error (device loop1): ext4_dx_csum_set:531: inode #2: comm syz.1.50: dir seems corrupt? Run e2fsck -D.