syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop6, logical block 10, lost async page write ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x42c9/0x5e70 Read of size 8 at addr ffff8880194e4738 by task syz-executor/12767 CPU: 0 PID: 12767 Comm: syz-executor Not tainted 6.1.0-rc5-next-20221118 #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+0x358/0xe40 ksys_write+0x12b/0x260 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f7051f645c3 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:00007ffce68b36e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ffce68b3d28 RCX: 00007f7051f645c3 RDX: 0000000000000004 RSI: 00007f705201aed9 RDI: 0000000000000003 RBP: 0000000000000002 R08: 0000000000000cf7 R09: 00007ffce69a4080 R10: 00007ffce69a4090 R11: 0000000000000246 R12: 00000000fffffff6 R13: 00007ffce68b4ef1 R14: 0000000000000000 R15: 000000000032a51a Allocated by task 12765: kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 __kasan_slab_alloc+0x5c/0x70 kmem_cache_alloc+0x1e0/0x410 __create_object+0x3d/0xc00 kmem_cache_alloc_lru+0x307/0x760 __d_alloc+0x31/0x9c0 d_alloc_parallel+0x10e/0x1530 lookup_open.isra.0+0x914/0x1250 path_openat+0x946/0x29b0 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+0x7cf/0x2070 __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+0x7cf/0x2070 __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 ffff8880194e4720 which belongs to the cache kmemleak_object of size 240 The buggy address is located 24 bytes inside of 240-byte region [ffff8880194e4720, ffff8880194e4810) The buggy address belongs to the physical page: page:00000000ea06ff75 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x194e4 anon flags: 0x100000000000200(slab|node=0|zone=1) raw: 0100000000000200 ffff88800844f780 ffffea0000381140 dead000000000003 raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880194e4600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880194e4680: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff8880194e4700: fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880194e4780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880194e4800: fb fb fc fc fc fc fc fc fc fc 00 00 00 00 00 00 ==================================================================