syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=40, nr_sectors = 4 limit=39 Buffer I/O error on dev loop6, logical block 10, lost async page write ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x42c5/0x5e70 Read of size 8 at addr ffff88801bbcb458 by task syz-executor/14222 CPU: 1 PID: 14222 Comm: syz-executor Not tainted 5.19.0-rc5-next-20220706 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x8b/0xb3 print_report.cold+0x5e/0x5e1 kasan_report+0xb1/0x1b0 __lock_acquire+0x42c5/0x5e70 lock_acquire+0x1a2/0x530 _raw_spin_lock_irq+0x32/0x50 kmemleak_scan+0x21d/0x16f0 kmemleak_write+0x56c/0x680 full_proxy_write+0x11d/0x190 vfs_write+0x264/0xac0 ksys_write+0x127/0x250 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7fb8058a95c3 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:00007fff360c88d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fff360c8f18 RCX: 00007fb8058a95c3 RDX: 0000000000000004 RSI: 00007fb80595fed9 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000c0b R09: 00007fff361f6080 R10: 00007fff361f6090 R11: 0000000000000246 R12: 00007fb8058abb10 R13: 00007fff360c9ee3 R14: 0000000000000000 R15: 00000000002f0bea Allocated by task 14224: kasan_save_stack+0x1e/0x40 __kasan_slab_alloc+0x66/0x80 kmem_cache_alloc+0x1b1/0x490 __create_object.isra.0+0x3d/0xc10 kmem_cache_alloc+0x247/0x490 __alloc_file+0x21/0x230 alloc_empty_file+0x6d/0x170 path_openat+0xe1/0x2890 do_filp_open+0x1aa/0x400 do_sys_openat2+0x16d/0x4c0 __x64_sys_openat+0x13f/0x1f0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x46/0xb0 Freed by task 13: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_set_free_info+0x20/0x30 __kasan_slab_free+0x108/0x190 kmem_cache_free+0xfb/0x600 rcu_core+0x7e2/0x2080 __do_softirq+0x1c8/0x8cc Last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0x97/0xa0 call_rcu+0x6a/0xa20 kmem_cache_free+0xc1/0x600 rcu_core+0x7e2/0x2080 __do_softirq+0x1c8/0x8cc Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0x97/0xa0 call_rcu+0x6a/0xa20 kfree+0xbb/0x5d0 security_cred_free+0xc0/0x120 put_cred_rcu+0x73/0x390 __put_cred+0x12e/0x180 revert_creds+0xaf/0xd0 do_faccessat+0x2e7/0x810 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x46/0xb0 The buggy address belongs to the object at ffff88801bbcb440 which belongs to the cache kmemleak_object of size 368 The buggy address is located 24 bytes inside of 368-byte region [ffff88801bbcb440, ffff88801bbcb5b0) The buggy address belongs to the physical page: page:0000000049e00961 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1bbca head:0000000049e00961 order:1 compound_mapcount:0 compound_pincount:0 flags: 0x100000000010200(slab|head|node=0|zone=1) raw: 0100000000010200 0000000000000000 dead000000000001 ffff88800784f780 raw: 0000000000000000 0000000000120012 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88801bbcb300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801bbcb380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88801bbcb400: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff88801bbcb480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801bbcb500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================