================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xc1f/0xc30 fs/ext4/xattr.c:2911 Read of size 4 at addr ffff8881d42ba000 by task syz-executor.0/373 CPU: 0 PID: 373 Comm: syz-executor.0 Not tainted 5.4.274-syzkaller-00002-g6f97bd951d82 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x241 lib/dump_stack.c:118 print_address_description+0x8c/0x600 mm/kasan/report.c:384 __kasan_report+0xf3/0x120 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 ext4_xattr_delete_inode+0xc1f/0xc30 fs/ext4/xattr.c:2911 ext4_evict_inode+0x1378/0x1ac0 fs/ext4/inode.c:318 evict+0x29b/0x6a0 fs/inode.c:575 d_delete_notify include/linux/fsnotify.h:224 [inline] vfs_rmdir+0x24b/0x3c0 fs/namei.c:4040 do_rmdir+0x2c1/0x580 fs/namei.c:4088 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7f506235a687 Code: 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 07 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffee1e11078 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f506235a687 RDX: 0000000000000200 RSI: 00007ffee1e12220 RDI: 00000000ffffff9c RBP: 00007f50623b7636 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffee1e12220 R13: 00007f50623b7636 R14: 00000000000064ab R15: 0000000000000008 Allocated by task 1: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2829 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842 prepare_creds+0x2c/0x580 kernel/cred.c:258 do_faccessat+0xa7/0x6f0 fs/open.c:360 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Freed by task 1: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:345 [inline] __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1455 [inline] slab_free_freelist_hook mm/slub.c:1494 [inline] slab_free mm/slub.c:3080 [inline] kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096 put_cred include/linux/cred.h:287 [inline] do_faccessat+0x52f/0x6f0 fs/open.c:439 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 The buggy address belongs to the object at ffff8881d42ba000 which belongs to the cache cred_jar of size 168 The buggy address is located 0 bytes inside of 168-byte region [ffff8881d42ba000, ffff8881d42ba0a8) The buggy address belongs to the page: page:ffffea000750ae80 refcount:1 mapcount:0 mapping:ffff8881f5cf9400 index:0x0 flags: 0x8000000000000200(slab) raw: 8000000000000200 dead000000000100 dead000000000122 ffff8881f5cf9400 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x18f/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893 alloc_slab_page+0x39/0x3c0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x440 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x2fe/0x490 mm/slub.c:2667 __slab_alloc+0x62/0xa0 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0x109/0x250 mm/slub.c:2842 prepare_creds+0x2c/0x580 kernel/cred.c:258 selinux_setprocattr+0x2e5/0xc20 security/selinux/hooks.c:6532 proc_pid_attr_write+0x2a6/0x2f0 fs/proc/base.c:2616 __vfs_write+0x103/0x750 fs/read_write.c:494 vfs_write+0x206/0x4e0 fs/read_write.c:558 ksys_write+0x199/0x2c0 fs/read_write.c:611 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] __free_pages_ok+0x847/0x950 mm/page_alloc.c:1438 free_the_page mm/page_alloc.c:4955 [inline] __free_pages mm/page_alloc.c:4961 [inline] free_pages+0xf6/0x1b0 mm/page_alloc.c:4969 stack_depot_save+0x42b/0x480 lib/stackdepot.c:300 save_stack mm/kasan/common.c:72 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x1d9/0x210 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2829 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842 kmem_cache_zalloc include/linux/slab.h:680 [inline] __kernfs_new_node+0xdb/0x6e0 fs/kernfs/dir.c:639 kernfs_new_node+0x130/0x230 fs/kernfs/dir.c:717 __kernfs_create_file+0x45/0x260 fs/kernfs/file.c:1001 sysfs_add_file_mode_ns+0x292/0x340 fs/sysfs/file.c:306 create_files fs/sysfs/group.c:63 [inline] internal_create_group+0x573/0xf00 fs/sysfs/group.c:148 loop_sysfs_init drivers/block/loop.c:863 [inline] loop_configure+0xbfa/0x1270 drivers/block/loop.c:1167 lo_ioctl+0x7d6/0x22e0 drivers/block/loop.c:1704 __blkdev_driver_ioctl block/ioctl.c:304 [inline] blkdev_ioctl+0x8f6/0x2cf0 block/ioctl.c:609 block_ioctl+0xaa/0xe0 fs/block_dev.c:1974 do_vfs_ioctl+0x742/0x1720 fs/ioctl.c:47 ksys_ioctl fs/ioctl.c:742 [inline] __do_sys_ioctl fs/ioctl.c:749 [inline] __se_sys_ioctl fs/ioctl.c:747 [inline] __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747 Memory state around the buggy address: ffff8881d42b9f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881d42b9f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881d42ba000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881d42ba080: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ffff8881d42ba100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================