================================================================== BUG: KASAN: use-after-free in ext4_htree_fill_tree+0x1316/0x13e0 fs/ext4/namei.c:1220 Read of size 1 at addr ffff888113945a67 by task syz-executor/487 CPU: 1 PID: 487 Comm: syz-executor Not tainted 5.10.222-syzkaller-1003210-gfd58936f3c1f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118 print_address_description+0x81/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0x179/0x1c0 mm/kasan/report.c:452 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306 ext4_htree_fill_tree+0x1316/0x13e0 fs/ext4/namei.c:1220 ext4_dx_readdir fs/ext4/dir.c:598 [inline] ext4_readdir+0x2dde/0x37c0 fs/ext4/dir.c:142 iterate_dir+0x265/0x580 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64+0x1c1/0x460 fs/readdir.c:354 __x64_sys_getdents64+0x7b/0x90 fs/readdir.c:354 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f80f0c59bf3 Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 f2 44 f8 ff 66 90 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 c7 c2 a8 ff ff ff f7 d8 RSP: 002b:00007fff107fde98 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00005555571524e0 RCX: 00007f80f0c59bf3 RDX: 0000000000008000 RSI: 00005555571524e0 RDI: 0000000000000005 RBP: 00005555571524b4 R08: 0000000000028b61 R09: 0000000000000000 R10: 00007f80f0d86ca0 R11: 0000000000000293 R12: ffffffffffffffa8 R13: 0000000000000010 R14: 00005555571524b0 R15: 000000000000b847 Allocated by task 438: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] __kasan_slab_alloc+0xb1/0xe0 mm/kasan/common.c:463 kasan_slab_alloc include/linux/kasan.h:244 [inline] slab_post_alloc_hook+0x61/0x2f0 mm/slab.h:583 slab_alloc_node mm/slub.c:2947 [inline] slab_alloc mm/slub.c:2955 [inline] kmem_cache_alloc+0x168/0x2e0 mm/slub.c:2960 getname_flags+0xba/0x520 fs/namei.c:141 user_path_at_empty+0x2d/0x50 fs/namei.c:2740 user_path_at include/linux/namei.h:60 [inline] vfs_statx+0x106/0x3b0 fs/stat.c:193 vfs_fstatat fs/stat.c:215 [inline] __do_sys_newfstatat fs/stat.c:383 [inline] __se_sys_newfstatat+0xc8/0x760 fs/stat.c:377 __x64_sys_newfstatat+0x9b/0xb0 fs/stat.c:377 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb Freed by task 438: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370 kasan_slab_free include/linux/kasan.h:220 [inline] slab_free_hook mm/slub.c:1595 [inline] slab_free_freelist_hook+0xc0/0x190 mm/slub.c:1621 slab_free mm/slub.c:3203 [inline] kmem_cache_free+0xa9/0x1e0 mm/slub.c:3219 putname fs/namei.c:262 [inline] filename_lookup+0x515/0x6f0 fs/namei.c:2470 user_path_at_empty+0x40/0x50 fs/namei.c:2740 user_path_at include/linux/namei.h:60 [inline] vfs_statx+0x106/0x3b0 fs/stat.c:193 vfs_fstatat fs/stat.c:215 [inline] __do_sys_newfstatat fs/stat.c:383 [inline] __se_sys_newfstatat+0xc8/0x760 fs/stat.c:377 __x64_sys_newfstatat+0x9b/0xb0 fs/stat.c:377 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb The buggy address belongs to the object at ffff888113945500 which belongs to the cache names_cache of size 4096 The buggy address is located 1383 bytes inside of 4096-byte region [ffff888113945500, ffff888113946500) The buggy address belongs to the page: page:ffffea00044e5000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x113940 head:ffffea00044e5000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100192900 raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 101, ts 4127708571, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x166/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x2d8c/0x2f30 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x435/0xaf0 mm/page_alloc.c:5348 allocate_slab mm/slub.c:1808 [inline] new_slab+0x80/0x400 mm/slub.c:1869 new_slab_objects mm/slub.c:2627 [inline] ___slab_alloc+0x302/0x4b0 mm/slub.c:2791 __slab_alloc+0x63/0xa0 mm/slub.c:2831 slab_alloc_node mm/slub.c:2913 [inline] slab_alloc mm/slub.c:2955 [inline] kmem_cache_alloc+0x1b9/0x2e0 mm/slub.c:2960 getname_flags+0xba/0x520 fs/namei.c:141 user_path_at_empty+0x2d/0x50 fs/namei.c:2740 user_path_at include/linux/namei.h:60 [inline] vfs_statx+0x106/0x3b0 fs/stat.c:193 vfs_fstatat fs/stat.c:215 [inline] __do_sys_newfstatat fs/stat.c:383 [inline] __se_sys_newfstatat+0xc8/0x760 fs/stat.c:377 __x64_sys_newfstatat+0x9b/0xb0 fs/stat.c:377 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb page_owner free stack trace missing Memory state around the buggy address: ffff888113945900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888113945980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888113945a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888113945a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888113945b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================