syz-executor.7: attempt to access beyond end of device loop7: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop7, logical block 10, lost async page write ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x42c9/0x5e70 Read of size 8 at addr ffff88801650a868 by task syz-executor/10961 CPU: 0 PID: 10961 Comm: syz-executor Not tainted 6.1.0-rc4-next-20221109 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0x8f/0xb7 print_report+0x175/0x478 kasan_report+0xbf/0x1c0 __lock_acquire+0x42c9/0x5e70 lock_acquire+0x1a6/0x530 _raw_spin_lock_irq+0x36/0x50 kmemleak_scan+0x1a0/0x1600 kmemleak_write+0x574/0x680 full_proxy_write+0x121/0x190 vfs_write+0x2cf/0xd90 ksys_write+0x12b/0x260 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7efdb0e255c3 Code: 16 00 00 00 eb ae 90 b8 6e 00 00 00 eb a6 e8 44 ef 04 00 0f 1f 40 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 55 c3 0f 1f 40 00 48 83 ec 28 48 89 54 24 18 RSP: 002b:00007ffeecfc4d38 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ffeecfc5378 RCX: 00007efdb0e255c3 RDX: 0000000000000004 RSI: 00007efdb0edbed9 RDI: 0000000000000003 RBP: 0000000000000002 R08: 00000000000009b5 R09: 00007ffeecfe2080 R10: 00007ffeecfe2090 R11: 0000000000000246 R12: 00000000fffffff6 R13: 00007ffeecfc5ef1 R14: 0000000000000000 R15: 000000000025ec86 Allocated by task 127: kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 __kasan_slab_alloc+0x5c/0x70 kmem_cache_alloc+0x1b1/0x3e0 __create_object+0x3d/0xc00 kmem_cache_alloc+0x23d/0x3e0 __alloc_file+0x21/0x240 alloc_empty_file+0x71/0x170 path_openat+0xd4/0x29b0 do_filp_open+0x1ba/0x410 do_sys_openat2+0x171/0x4c0 __x64_sys_openat+0x143/0x200 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc Freed by task 13: kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 kasan_save_free_info+0x2e/0x50 __kasan_slab_free+0x10a/0x190 kmem_cache_free+0xfb/0x610 rcu_core+0x7e2/0x2090 __do_softirq+0x1c7/0x8f9 Last potentially related work creation: kasan_save_stack+0x22/0x50 __kasan_record_aux_stack+0x95/0xb0 __call_rcu_common.constprop.0+0x6a/0xa40 kmem_cache_free+0xc1/0x610 rcu_core+0x7e2/0x2090 __do_softirq+0x1c7/0x8f9 Second to last potentially related work creation: kasan_save_stack+0x22/0x50 __kasan_record_aux_stack+0x95/0xb0 __call_rcu_common.constprop.0+0x6a/0xa40 __kmem_cache_free+0x95/0x410 security_cred_free+0xc4/0x130 put_cred_rcu+0x77/0x3a0 __put_cred+0x132/0x180 revert_creds+0xb3/0xd0 do_faccessat+0x2db/0x7f0 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc The buggy address belongs to the object at ffff88801650a850 which belongs to the cache kmemleak_object of size 240 The buggy address is located 24 bytes inside of 240-byte region [ffff88801650a850, ffff88801650a940) The buggy address belongs to the physical page: page:000000009569420d refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1650a flags: 0x100000000000200(slab|node=0|zone=1) raw: 0100000000000200 ffff88800804f780 ffffea00003b2400 dead000000000004 raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88801650a700: fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb ffff88801650a780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801650a800: fb fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb ^ ffff88801650a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801650a900: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================