audit: type=1804 audit(1545153240.427:40): pid=8058 uid=0 auid=4294967295 ses=4294967295 subj=_ op=invalid_pcr cause=open_writers comm="syz-executor1" name="/root/syzkaller-testdir173247712/syzkaller.qk9XgL/12/file0" dev="sda1" ino=16550 res=1 ================================================================== BUG: KASAN: use-after-free in tipc_group_bc_cong+0x327/0x3f0 net/tipc/group.c:448 Read of size 2 at addr ffff8881d4ffcd74 by task syz-executor0/8033 CPU: 0 PID: 8033 Comm: syz-executor0 Not tainted 4.20.0-rc7+ #155 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 kasan: CONFIG_KASAN_INLINE enabled __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:431 tipc_group_bc_cong+0x327/0x3f0 net/tipc/group.c:448 tipc_send_group_bcast+0x50a/0xd90 net/tipc/socket.c:1023 kasan: GPF could be caused by NULL-ptr deref or user memory access __tipc_sendmsg+0xeec/0x1d40 net/tipc/socket.c:1307 tipc_sendmsg+0x50/0x70 net/tipc/socket.c:1272 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 8038 Comm: syz-executor0 Not tainted 4.20.0-rc7+ #155 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:tipc_group_update_bc_members+0x38/0x1f0 net/tipc/group.c:389 Code: 54 53 48 83 ec 18 89 55 c4 89 75 d0 e8 31 b8 db f9 49 8d 4e 72 48 b8 00 00 00 00 00 fc ff df 48 89 ca 48 89 4d c8 48 c1 ea 03 <0f> b6 14 02 48 89 c8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 76 RSP: 0018:ffff88817f74f370 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000072 RDX: 000000000000000e RSI: ffffffff87a3cc3f RDI: 0000000000000000 RBP: ffff88817f74f3b0 R08: ffff8881c2d56400 R09: ffffed103b5e5b5f R10: ffffed103b5e5b5f R11: ffff8881daf2dafb R12: ffff88817f74f618 R13: ffff8881b9ce761c R14: 0000000000000000 R15: 0000000000000000 FS: 00007f1546265700(0000) GS:ffff8881daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 CR2: 0000000020000240 CR3: 00000001bd689000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tipc_send_group_bcast+0xa71/0xd90 net/tipc/socket.c:1056 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 __tipc_sendmsg+0xeec/0x1d40 net/tipc/socket.c:1307 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457669 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1546285c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457669 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000004 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f15462866d4 R13: 00000000004c44f4 R14: 00000000004d7518 R15: 00000000ffffffff Allocated by task 8033: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620 kmalloc include/linux/slab.h:546 [inline] kzalloc include/linux/slab.h:741 [inline] tipc_group_create+0x152/0xa70 net/tipc/group.c:171 tipc_sk_join net/tipc/socket.c:2829 [inline] tipc_setsockopt+0x2d1/0xd70 net/tipc/socket.c:2944 __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe tipc_sendmsg+0x50/0x70 net/tipc/socket.c:1272 Freed by task 8038: sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 save_stack+0x43/0xd0 mm/kasan/kasan.c:448 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 tipc_group_delete+0x2e4/0x3f0 net/tipc/group.c:227 tipc_sk_leave+0x113/0x220 net/tipc/socket.c:2863 tipc_setsockopt+0x97d/0xd70 net/tipc/socket.c:2947 __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8881d4ffcd00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 116 bytes inside of 192-byte region [ffff8881d4ffcd00, ffff8881d4ffcdc0) The buggy address belongs to the page: page:ffffea000753ff00 count:1 mapcount:0 mapping:ffff8881da800040 index:0x0 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea00074eb908 ffffea000752f708 ffff8881da800040 raw: 0000000000000000 ffff8881d4ffc000 0000000100000010 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881d4ffcc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 ffff8881d4ffcc80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 >ffff8881d4ffcd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881d4ffcd80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881d4ffce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457669 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1546264c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457669 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000007 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f15462656d4 R13: 00000000004c44f4 R14: 00000000004d7518 R15: 00000000ffffffff Modules linked in: kobject: 'loop2' (0000000088e81f02): kobject_uevent_env kobject: 'loop2' (0000000088e81f02): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop2' (0000000088e81f02): kobject_uevent_env kobject: 'loop2' (0000000088e81f02): fill_kobj_path: path = '/devices/virtual/block/loop2' ---[ end trace fd2ebb0cac6102d2 ]--- RIP: 0010:tipc_group_update_bc_members+0x38/0x1f0 net/tipc/group.c:389 Code: 54 53 48 83 ec 18 89 55 c4 89 75 d0 e8 31 b8 db f9 49 8d 4e 72 48 b8 00 00 00 00 00 fc ff df 48 89 ca 48 89 4d c8 48 c1 ea 03 <0f> b6 14 02 48 89 c8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 76 RSP: 0018:ffff88817f74f370 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000072 kobject: 'loop1' (0000000001cb21dd): kobject_uevent_env RDX: 000000000000000e RSI: ffffffff87a3cc3f RDI: 0000000000000000 RBP: ffff88817f74f3b0 R08: ffff8881c2d56400 R09: ffffed103b5e5b5f R10: ffffed103b5e5b5f R11: ffff8881daf2dafb R12: ffff88817f74f618 R13: ffff8881b9ce761c R14: 0000000000000000 R15: 0000000000000000 FS: 00007f1546265700(0000) GS:ffff8881daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000625208 CR3: 00000001bd689000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 kobject: 'loop1' (0000000001cb21dd): fill_kobj_path: path = '/devices/virtual/block/loop1'