================================================================== BUG: KASAN: slab-use-after-free in ext4_insert_dentry+0x36a/0x6d0 fs/ext4/namei.c:2119 Write of size 250 at addr ffff88806afc1f18 by task syz-executor132/5824 CPU: 1 UID: 0 PID: 5824 Comm: syz-executor132 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 ext4_insert_dentry+0x36a/0x6d0 fs/ext4/namei.c:2119 add_dirent_to_buf+0x3d9/0x750 fs/ext4/namei.c:2164 make_indexed_dir+0xf98/0x1600 fs/ext4/namei.c:2361 ext4_add_entry+0xcf7/0xfa0 fs/ext4/namei.c:2462 ext4_mkdir+0x554/0xcf0 fs/ext4/namei.c:3039 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4311 do_mkdirat+0x264/0x3a0 fs/namei.c:4334 __do_sys_mkdirat fs/namei.c:4349 [inline] __se_sys_mkdirat fs/namei.c:4347 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4347 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f774e5d8d39 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 1c 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff907f19e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007f774e5d8d39 RDX: 0000000000000000 RSI: 00000000200005c0 RDI: 00000000ffffff9c RBP: 0000000000000004 R08: 00007fff907f1a18 R09: 00007fff907f1a18 R10: 00007fff907f1a18 R11: 0000000000000246 R12: 00007fff907f1a40 R13: 00007f774e64e5e0 R14: 431bde82d7b634db R15: 00007fff907f1a20 The buggy address belongs to the physical page: page: refcount:3 mapcount:0 mapping:ffff888148c94d78 index:0x3f pfn:0x6afc1 memcg:ffff888140adc000 aops:def_blk_aops ino:700000 dentry name(?):"" flags: 0xfff00000004114(referenced|dirty|active|private|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000004114 0000000000000000 dead000000000122 ffff888148c94d78 raw: 000000000000003f ffff888075c4d9f8 00000003ffffffff ffff888140adc000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x148c40(GFP_NOFS|__GFP_NOFAIL|__GFP_COMP|__GFP_HARDWALL), pid 5824, tgid 5824 (syz-executor132), ts 70184402240, free_ts 70183711372 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3474 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_pages_noprof mm/mempolicy.c:2344 [inline] folio_alloc_noprof+0x128/0x180 mm/mempolicy.c:2351 filemap_alloc_folio_noprof+0xdf/0x500 mm/filemap.c:1009 __filemap_get_folio+0x446/0xbd0 mm/filemap.c:1951 grow_dev_folio fs/buffer.c:1039 [inline] grow_buffers fs/buffer.c:1105 [inline] __getblk_slow fs/buffer.c:1131 [inline] bdev_getblk+0x1d8/0x550 fs/buffer.c:1431 getblk_unmovable include/linux/buffer_head.h:369 [inline] ext4_getblk+0x31b/0x880 fs/ext4/inode.c:864 ext4_bread+0x2e/0x180 fs/ext4/inode.c:912 ext4_append+0x327/0x5c0 fs/ext4/namei.c:83 make_indexed_dir+0x523/0x1600 fs/ext4/namei.c:2282 ext4_add_entry+0xcf7/0xfa0 fs/ext4/namei.c:2462 ext4_mkdir+0x554/0xcf0 fs/ext4/namei.c:3039 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4311 do_mkdirat+0x264/0x3a0 fs/namei.c:4334 page last free pid 0 tgid 0 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0xde3/0x1130 mm/page_alloc.c:2657 skb_free_frag include/linux/skbuff.h:3437 [inline] skb_free_head net/core/skbuff.c:1096 [inline] skb_release_data+0x6dc/0x8a0 net/core/skbuff.c:1125 skb_release_all net/core/skbuff.c:1190 [inline] __kfree_skb+0x55/0x70 net/core/skbuff.c:1204 tcp_rcv_established+0xfb7/0x1f20 net/ipv4/tcp_input.c:6174 tcp_v4_do_rcv+0x96d/0xc70 net/ipv4/tcp_ipv4.c:1916 tcp_v4_rcv+0x2dc0/0x37f0 net/ipv4/tcp_ipv4.c:2351 ip_protocol_deliver_rcu+0x22e/0x440 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 ip_local_deliver net/ipv4/ip_input.c:254 [inline] dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish+0x3be/0x4f0 net/ipv4/ip_input.c:578 ip_list_rcv_finish net/ipv4/ip_input.c:628 [inline] ip_sublist_rcv+0x75d/0xab0 net/ipv4/ip_input.c:636 ip_list_rcv+0x42b/0x480 net/ipv4/ip_input.c:670 __netif_receive_skb_list_ptype net/core/dev.c:5715 [inline] __netif_receive_skb_list_core+0x94e/0x980 net/core/dev.c:5762 __netif_receive_skb_list net/core/dev.c:5814 [inline] netif_receive_skb_list_internal+0xa51/0xe30 net/core/dev.c:5905 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x2b5/0x870 net/core/dev.c:6256 virtqueue_napi_complete drivers/net/virtio_net.c:758 [inline] virtnet_poll+0x2de9/0x39b0 drivers/net/virtio_net.c:3013 Memory state around the buggy address: ffff88806afc1f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806afc1f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88806afc2000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806afc2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff88806afc2100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================