================================================================== BUG: KASAN: use-after-free in memcpy include/linux/fortify-string.h:191 [inline] BUG: KASAN: use-after-free in __d_alloc+0x19a/0x950 fs/dcache.c:1775 Read of size 5 at addr ffff8880215de820 by task kdevtmpfs/22 CPU: 1 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x6c/0x2d6 mm/kasan/report.c:256 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 memcpy+0x20/0x60 mm/kasan/shadow.c:65 memcpy include/linux/fortify-string.h:191 [inline] __d_alloc+0x19a/0x950 fs/dcache.c:1775 d_alloc+0x4a/0x230 fs/dcache.c:1823 __lookup_hash+0xc8/0x180 fs/namei.c:1554 kern_path_locked+0x17e/0x320 fs/namei.c:2567 handle_remove+0xa2/0x5fe drivers/base/devtmpfs.c:312 handle drivers/base/devtmpfs.c:382 [inline] devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline] devtmpfsd+0x1b9/0x2a3 drivers/base/devtmpfs.c:437 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 22: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x80/0xa0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc mm/slab.c:3323 [inline] kmem_cache_alloc+0x25f/0x540 mm/slab.c:3507 getname_kernel+0x4e/0x370 fs/namei.c:226 kern_path_locked+0x71/0x320 fs/namei.c:2558 handle_remove+0xa2/0x5fe drivers/base/devtmpfs.c:312 handle drivers/base/devtmpfs.c:382 [inline] devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline] devtmpfsd+0x1b9/0x2a3 drivers/base/devtmpfs.c:437 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Freed by task 22: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xd1/0x110 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] __cache_free mm/slab.c:3445 [inline] kmem_cache_free+0x6c/0x200 mm/slab.c:3740 putname.part.0+0xe1/0x120 fs/namei.c:270 putname include/linux/err.h:41 [inline] filename_parentat fs/namei.c:2547 [inline] kern_path_locked+0xc2/0x320 fs/namei.c:2558 handle_remove+0xa2/0x5fe drivers/base/devtmpfs.c:312 handle drivers/base/devtmpfs.c:382 [inline] devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline] devtmpfsd+0x1b9/0x2a3 drivers/base/devtmpfs.c:437 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff8880215de800 which belongs to the cache names_cache of size 4096 The buggy address is located 32 bytes inside of 4096-byte region [ffff8880215de800, ffff8880215df800) The buggy address belongs to the page: page:ffffea0000857780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x215de head:ffffea0000857780 order:1 compound_mapcount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea000084a108 ffffea0001cd1c88 ffff8880114b9600 raw: 0000000000000000 ffff8880215de800 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 2968, ts 1690412692681, free_ts 1690402831228 prep_new_page mm/page_alloc.c:2424 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4151 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5373 __alloc_pages_node include/linux/gfp.h:570 [inline] kmem_getpages mm/slab.c:1377 [inline] cache_grow_begin+0x75/0x460 mm/slab.c:2593 cache_alloc_refill+0x27f/0x380 mm/slab.c:2965 ____cache_alloc mm/slab.c:3048 [inline] ____cache_alloc mm/slab.c:3031 [inline] __do_cache_alloc mm/slab.c:3275 [inline] slab_alloc mm/slab.c:3316 [inline] kmem_cache_alloc+0x454/0x540 mm/slab.c:3507 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags include/linux/audit.h:319 [inline] getname+0x8e/0xd0 fs/namei.c:217 do_sys_openat2+0xf5/0x4d0 fs/open.c:1194 do_sys_open fs/open.c:1216 [inline] __do_sys_open fs/open.c:1224 [inline] __se_sys_open fs/open.c:1220 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1220 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1338 [inline] free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1389 free_unref_page_prepare mm/page_alloc.c:3315 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3394 slab_destroy mm/slab.c:1627 [inline] slabs_destroy+0x89/0xc0 mm/slab.c:1647 cache_flusharray mm/slab.c:3418 [inline] ___cache_free+0x4c6/0x610 mm/slab.c:3480 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x4e/0x110 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x92/0xa0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc mm/slab.c:3323 [inline] __do_kmalloc mm/slab.c:3700 [inline] __kmalloc+0x284/0x4d0 mm/slab.c:3711 kmalloc include/linux/slab.h:596 [inline] tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x272/0x380 security/tomoyo/file.c:771 tomoyo_file_open security/tomoyo/tomoyo.c:311 [inline] tomoyo_file_open+0xa3/0xd0 security/tomoyo/tomoyo.c:306 security_file_open+0x45/0xb0 security/security.c:1634 do_dentry_open+0x353/0x11d0 fs/open.c:809 do_open fs/namei.c:3426 [inline] path_openat+0x1c9a/0x2740 fs/namei.c:3559 do_filp_open+0x1aa/0x400 fs/namei.c:3586 do_sys_openat2+0x16d/0x4d0 fs/open.c:1200 Memory state around the buggy address: ffff8880215de700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880215de780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880215de800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880215de880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880215de900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================