================================================================== BUG: KASAN: use-after-free in dx_insert_block+0xd9/0x240 fs/ext4/namei.c:1387 Read of size 157024 at addr ffff888117146028 by task syz.3.158/1295 CPU: 0 PID: 1295 Comm: syz.3.158 Not tainted 6.1.145-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x71/0x210 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:427 kasan_report+0x122/0x150 mm/kasan/report.c:531 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+0xd9/0x240 fs/ext4/namei.c:1387 do_split+0x19f0/0x1d90 fs/ext4/namei.c:2080 make_indexed_dir+0xe06/0x14a0 fs/ext4/namei.c:2392 ext4_add_entry+0xb45/0xd70 fs/ext4/namei.c:2504 __ext4_link+0x4d7/0x770 fs/ext4/namei.c:3522 ext4_link+0x1de/0x270 fs/ext4/namei.c:3563 vfs_link+0x64b/0x800 fs/namei.c:4599 do_linkat+0x1f8/0x490 fs/namei.c:4670 __do_sys_link fs/namei.c:4704 [inline] __se_sys_link fs/namei.c:4702 [inline] __x64_sys_link+0x86/0x90 fs/namei.c:4702 x64_sys_call+0x266/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:87 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f9676b8e969 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:00007f9677a06038 EFLAGS: 00000246 ORIG_RAX: 0000000000000056 RAX: ffffffffffffffda RBX: 00007f9676db5fa0 RCX: 00007f9676b8e969 RDX: 0000000000000000 RSI: 0000200000000bc0 RDI: 0000200000001240 RBP: 00007f9676c10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9676db5fa0 R15: 00007ffc2a0cca58 The buggy address belongs to the physical page: page:ffffea00045c5180 refcount:3 mapcount:1 mapping:ffff888100489290 index:0x1 pfn:0x117146 memcg:ffff8881001fe000 aops:def_blk_aops ino:700003 flags: 0x460000000032205e(referenced|uptodate|dirty|lru|workingset|private|mappedtodisk|unevictable|mlocked|zone=1) raw: 460000000032205e dead000000000100 dead000000000001 ffff888100489290 raw: 0000000000000001 ffff8881218bbdc8 0000000300000000 ffff8881001fe000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x152c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 624, tgid 624 (udevd), ts 99793615669, free_ts 99765310595 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1d0/0x1f0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x2e63/0x2ef0 mm/page_alloc.c:4328 __alloc_pages+0x235/0x4b0 mm/page_alloc.c:5614 __folio_alloc+0x12/0x40 mm/page_alloc.c:5646 __folio_alloc_node include/linux/gfp.h:246 [inline] folio_alloc include/linux/gfp.h:275 [inline] filemap_alloc_folio include/linux/pagemap.h:507 [inline] page_cache_ra_unbounded+0x17a/0x4a0 mm/readahead.c:248 do_page_cache_ra mm/readahead.c:300 [inline] force_page_cache_ra mm/readahead.c:331 [inline] page_cache_sync_ra+0x3e3/0x490 mm/readahead.c:713 page_cache_sync_readahead include/linux/pagemap.h:1248 [inline] filemap_get_pages mm/filemap.c:2665 [inline] filemap_read+0x5e4/0x2170 mm/filemap.c:2759 blkdev_read_iter+0x41e/0x560 block/fops.c:614 call_read_iter include/linux/fs.h:2259 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x41e/0x8c0 fs/read_write.c:470 ksys_read+0x140/0x240 fs/read_write.c:613 __do_sys_read fs/read_write.c:623 [inline] __se_sys_read fs/read_write.c:621 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:621 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:1 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1532 [inline] free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3384 free_unref_page+0x33/0x390 mm/page_alloc.c:3479 free_the_page mm/page_alloc.c:754 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:5703 __free_slab+0xca/0x1a0 mm/slub.c:2016 free_slab mm/slub.c:2031 [inline] discard_slab+0x29/0x40 mm/slub.c:2037 __slab_free+0x201/0x280 mm/slub.c:3574 do_slab_free mm/slub.c:3615 [inline] ___cache_free+0xbf/0xd0 mm/slub.c:3668 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0xc6/0x140 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] kmem_cache_alloc_node+0x189/0x2e0 mm/slub.c:3443 __alloc_skb+0xdf/0x7e0 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1271 [inline] nlmsg_new include/net/netlink.h:991 [inline] netlink_ack+0x372/0x1100 net/netlink/af_netlink.c:2430 netlink_rcv_skb+0x277/0x440 net/netlink/af_netlink.c:2499 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6171 Memory state around the buggy address: ffff888117146f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888117146f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888117147000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888117147080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff888117147100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ================================================================== EXT4-fs error (device loop3): ext4_dx_csum_set:531: inode #2: comm syz.3.158: dir seems corrupt? Run e2fsck -D.