================================================================== BUG: KASAN: slab-use-after-free in ext4_insert_dentry+0x3cd/0x780 fs/ext4/namei.c:2119 Write of size 251 at addr ffff8880357b1f14 by task syz-executor285/5830 CPU: 1 UID: 0 PID: 5830 Comm: syz-executor285 Not tainted 6.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 ext4_insert_dentry+0x3cd/0x780 fs/ext4/namei.c:2119 add_dirent_to_buf+0x315/0x660 fs/ext4/namei.c:2164 make_indexed_dir+0xcaf/0x1280 fs/ext4/namei.c:2361 ext4_add_entry+0xb36/0xd30 fs/ext4/namei.c:2462 ext4_add_nondir+0x8d/0x290 fs/ext4/namei.c:2803 ext4_symlink+0xa10/0xda0 fs/ext4/namei.c:3440 vfs_symlink+0x137/0x2e0 fs/namei.c:4671 do_symlinkat+0x222/0x3a0 fs/namei.c:4697 __do_sys_symlink fs/namei.c:4718 [inline] __se_sys_symlink fs/namei.c:4716 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4716 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: 0033:0x7f7187546489 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 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:00007ffdd41c9608 EFLAGS: 00000246 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7187546489 RDX: 0000000000000000 RSI: 0000400000000cc0 RDI: 0000400000000dc0 RBP: 0000000000000000 R08: 00007ffdd41c9660 R09: 00007ffdd41c9660 R10: 00007ffdd41c9660 R11: 0000000000000246 R12: 00007ffdd41c9660 R13: 00007ffdd41c9740 R14: 431bde82d7b634db R15: 00007f718758f01d The buggy address belongs to the physical page: page: refcount:3 mapcount:0 mapping:ffff88802384cd78 index:0x3f pfn:0x357b1 memcg:ffff88801c2ec000 aops:def_blk_aops ino:700000 dentry name(?):"" flags: 0xfff00000004114(referenced|dirty|active|private|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000004114 0000000000000000 dead000000000122 ffff88802384cd78 raw: 000000000000003f ffff888054330828 00000003ffffffff ffff88801c2ec000 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 5830, tgid 5830 (syz-executor285), ts 81686823471, free_ts 81454601852 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_frozen_pages_noprof mm/mempolicy.c:2341 [inline] alloc_pages_noprof+0x121/0x190 mm/mempolicy.c:2361 folio_alloc_noprof+0x1e/0x30 mm/mempolicy.c:2371 filemap_alloc_folio_noprof+0xe1/0x540 mm/filemap.c:1019 __filemap_get_folio+0x438/0xae0 mm/filemap.c:1970 grow_dev_folio fs/buffer.c:1039 [inline] grow_buffers fs/buffer.c:1105 [inline] __getblk_slow fs/buffer.c:1131 [inline] bdev_getblk+0x1d4/0x670 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+0x3ff/0x1280 fs/ext4/namei.c:2282 ext4_add_entry+0xb36/0xd30 fs/ext4/namei.c:2462 ext4_add_nondir+0x8d/0x290 fs/ext4/namei.c:2803 ext4_symlink+0xa10/0xda0 fs/ext4/namei.c:3440 page last free pid 5830 tgid 5830 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe04/0x10e0 mm/page_alloc.c:2660 __slab_free+0x2c2/0x380 mm/slub.c:4520 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] __kmalloc_cache_noprof+0x1d9/0x390 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:901 [inline] tomoyo_print_header security/tomoyo/audit.c:156 [inline] tomoyo_init_log+0x1c1/0x20d0 security/tomoyo/audit.c:255 tomoyo_supervisor+0x3b2/0x1860 security/tomoyo/common.c:2198 tomoyo_audit_path_log security/tomoyo/file.c:168 [inline] tomoyo_path_permission+0x243/0x360 security/tomoyo/file.c:587 tomoyo_check_open_permission+0x45e/0x4f0 security/tomoyo/file.c:780 security_file_open+0xac/0x250 security/security.c:3114 do_dentry_open+0x320/0x1960 fs/open.c:933 vfs_open+0x3b/0x370 fs/open.c:1086 do_open fs/namei.c:3830 [inline] path_openat+0x2c81/0x3590 fs/namei.c:3989 do_filp_open+0x27f/0x4e0 fs/namei.c:4016 do_sys_openat2+0x13e/0x1d0 fs/open.c:1428 Memory state around the buggy address: ffff8880357b1f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880357b1f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880357b2000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880357b2080: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa ffff8880357b2100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================