================================================================== BUG: KASAN: use-after-free in bdev_free_inode+0x202/0x220 block/bdev.c:407 Read of size 8 at addr ffff88801203a148 by task syz-executor.3/19644 CPU: 0 PID: 19644 Comm: syz-executor.3 Not tainted 5.15.0-rc4-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/0x309 mm/kasan/report.c:256 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 bdev_free_inode+0x202/0x220 block/bdev.c:407 i_callback+0x3f/0x70 fs/inode.c:226 rcu_do_batch kernel/rcu/tree.c:2508 [inline] rcu_core+0x7ab/0x1470 kernel/rcu/tree.c:2743 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x45/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0023:0xf6f78700 Code: 04 24 89 f8 8b 55 fc 8b 3f 8b 58 04 8b 6c 24 1c 8b 44 24 10 89 54 24 04 66 90 8d 55 f8 39 3c 24 89 54 24 08 89 f2 19 da 72 5c <83> e8 08 89 da 39 cf 1b 54 24 04 73 24 89 74 24 04 8d b4 26 00 00 RSP: 002b:00000000f75e9a30 EFLAGS: 00000246 RAX: 00000000f6d558a0 RBX: 00000000ffffffff RCX: 000000008195f1b6 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 000000008195f52a RBP: 00000000f6d55840 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 19642: 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_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0xa4/0xd0 mm/kasan/common.c:522 kmalloc_node include/linux/slab.h:609 [inline] kzalloc_node include/linux/slab.h:732 [inline] __alloc_disk_node+0x77/0x580 block/genhd.c:1238 __blk_mq_alloc_disk+0xed/0x160 block/blk-mq.c:3140 loop_add+0x340/0x960 drivers/block/loop.c:2344 loop_control_ioctl+0x130/0x4a0 drivers/block/loop.c:2512 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:972 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Freed by task 19642: 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+0xff/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1700 [inline] slab_free_freelist_hook+0x81/0x190 mm/slub.c:1725 slab_free mm/slub.c:3483 [inline] kfree+0xe4/0x530 mm/slub.c:4543 __alloc_disk_node+0x474/0x580 block/genhd.c:1275 __blk_mq_alloc_disk+0xed/0x160 block/blk-mq.c:3140 loop_add+0x340/0x960 drivers/block/loop.c:2344 loop_control_ioctl+0x130/0x4a0 drivers/block/loop.c:2512 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:972 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe9/0x110 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:2987 [inline] call_rcu+0xb1/0x750 kernel/rcu/tree.c:3067 rxrpc_put_local+0xa1/0xc0 net/rxrpc/local_object.c:322 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Second to last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe9/0x110 mm/kasan/generic.c:348 insert_work+0x48/0x370 kernel/workqueue.c:1353 __queue_work+0x5ca/0xee0 kernel/workqueue.c:1519 queue_work_on+0xee/0x110 kernel/workqueue.c:1546 queue_work include/linux/workqueue.h:502 [inline] rxrpc_queue_local+0xb3/0x130 net/rxrpc/local_object.c:300 rxrpc_unuse_local+0x59/0x60 net/rxrpc/local_object.c:352 rxrpc_release_sock net/rxrpc/af_rxrpc.c:890 [inline] rxrpc_release+0x29a/0x5a0 net/rxrpc/af_rxrpc.c:917 __sock_release net/socket.c:649 [inline] sock_release+0x87/0x1b0 net/socket.c:677 afs_close_socket+0x1cc/0x330 fs/afs/rxrpc.c:125 afs_net_exit+0x175/0x320 fs/afs/main.c:158 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:168 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:591 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 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 ffff88801203a000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 328 bytes inside of 1024-byte region [ffff88801203a000, ffff88801203a400) The buggy address belongs to the page: page:ffffea0000480e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12038 head:ffffea0000480e00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010c41dc0 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6534, ts 131150960444, free_ts 131141163617 prep_new_page mm/page_alloc.c:2424 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4153 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5375 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2197 alloc_slab_page mm/slub.c:1763 [inline] allocate_slab mm/slub.c:1900 [inline] new_slab+0x319/0x490 mm/slub.c:1963 ___slab_alloc+0x921/0xfe0 mm/slub.c:2994 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3081 slab_alloc_node mm/slub.c:3172 [inline] __kmalloc_node_track_caller+0x2d2/0x340 mm/slub.c:4936 kmalloc_reserve net/core/skbuff.c:355 [inline] __alloc_skb+0xde/0x340 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1116 [inline] __tcp_send_ack.part.0+0x67/0x7a0 net/ipv4/tcp_output.c:3946 __tcp_send_ack net/ipv4/tcp_output.c:3978 [inline] tcp_send_ack+0x7d/0xa0 net/ipv4/tcp_output.c:3978 tcp_cleanup_rbuf+0x464/0x5a0 net/ipv4/tcp.c:1601 tcp_recvmsg_locked+0x7a2/0x2320 net/ipv4/tcp.c:2522 tcp_recvmsg+0x134/0x550 net/ipv4/tcp.c:2552 inet_recvmsg+0x11b/0x5e0 net/ipv4/af_inet.c:852 sock_recvmsg_nosec net/socket.c:944 [inline] sock_recvmsg net/socket.c:962 [inline] sock_recvmsg net/socket.c:958 [inline] sock_read_iter+0x33c/0x470 net/socket.c:1035 call_read_iter include/linux/fs.h:2157 [inline] new_sync_read+0x5ba/0x6e0 fs/read_write.c:404 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 skb_free_frag include/linux/skbuff.h:2912 [inline] skb_free_head net/core/skbuff.c:652 [inline] skb_release_data+0x61f/0x790 net/core/skbuff.c:676 skb_release_all net/core/skbuff.c:741 [inline] __kfree_skb+0x46/0x60 net/core/skbuff.c:755 sk_eat_skb include/net/sock.h:2628 [inline] tcp_recvmsg_locked+0x12f7/0x2320 net/ipv4/tcp.c:2506 tcp_recvmsg+0x134/0x550 net/ipv4/tcp.c:2552 inet_recvmsg+0x11b/0x5e0 net/ipv4/af_inet.c:852 sock_recvmsg_nosec net/socket.c:944 [inline] sock_recvmsg net/socket.c:962 [inline] sock_recvmsg net/socket.c:958 [inline] sock_read_iter+0x33c/0x470 net/socket.c:1035 call_read_iter include/linux/fs.h:2157 [inline] new_sync_read+0x5ba/0x6e0 fs/read_write.c:404 vfs_read+0x35c/0x600 fs/read_write.c:485 ksys_read+0x1ee/0x250 fs/read_write.c:623 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 Memory state around the buggy address: ffff88801203a000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801203a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801203a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801203a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801203a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 04 24 add $0x24,%al 2: 89 f8 mov %edi,%eax 4: 8b 55 fc mov -0x4(%rbp),%edx 7: 8b 3f mov (%rdi),%edi 9: 8b 58 04 mov 0x4(%rax),%ebx c: 8b 6c 24 1c mov 0x1c(%rsp),%ebp 10: 8b 44 24 10 mov 0x10(%rsp),%eax 14: 89 54 24 04 mov %edx,0x4(%rsp) 18: 66 90 xchg %ax,%ax 1a: 8d 55 f8 lea -0x8(%rbp),%edx 1d: 39 3c 24 cmp %edi,(%rsp) 20: 89 54 24 08 mov %edx,0x8(%rsp) 24: 89 f2 mov %esi,%edx 26: 19 da sbb %ebx,%edx 28: 72 5c jb 0x86 * 2a: 83 e8 08 sub $0x8,%eax <-- trapping instruction 2d: 89 da mov %ebx,%edx 2f: 39 cf cmp %ecx,%edi 31: 1b 54 24 04 sbb 0x4(%rsp),%edx 35: 73 24 jae 0x5b 37: 89 74 24 04 mov %esi,0x4(%rsp) 3b: 8d .byte 0x8d 3c: b4 26 mov $0x26,%ah