================================================================== BUG: KASAN: use-after-free in sctp_sock_dump+0xaa3/0xb20 net/sctp/diag.c:311 Read of size 8 at addr ffff88808231c498 by task syz-executor.5/28263 CPU: 0 PID: 28263 Comm: syz-executor.5 Not tainted 5.4.0-rc5 #0 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:634 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 sctp_sock_dump+0xaa3/0xb20 net/sctp/diag.c:311 sctp_for_each_transport+0x2b4/0x350 net/sctp/socket.c:5404 sctp_diag_dump+0x33e/0x450 net/sctp/diag.c:513 __inet_diag_dump+0x9e/0x130 net/ipv4/inet_diag.c:1055 inet_diag_dump+0x9b/0x110 net/ipv4/inet_diag.c:1071 netlink_dump+0x558/0xfb0 net/netlink/af_netlink.c:2244 __netlink_dump_start+0x5b1/0x7d0 net/netlink/af_netlink.c:2352 netlink_dump_start include/linux/netlink.h:233 [inline] inet_diag_handler_cmd+0x262/0x320 net/ipv4/inet_diag.c:1176 __sock_diag_cmd net/core/sock_diag.c:233 [inline] sock_diag_rcv_msg+0x319/0x410 net/core/sock_diag.c:264 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 sock_diag_rcv+0x2b/0x40 net/core/sock_diag.c:275 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 sock_write_iter+0x27c/0x3e0 net/socket.c:989 call_write_iter include/linux/fs.h:1895 [inline] do_iter_readv_writev+0x5f8/0x8f0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x184/0x610 fs/read_write.c:951 compat_writev+0x1f1/0x390 fs/read_write.c:1295 do_compat_writev+0xf5/0x1f0 fs/read_write.c:1316 __do_compat_sys_writev fs/read_write.c:1327 [inline] __se_compat_sys_writev fs/read_write.c:1323 [inline] __ia32_compat_sys_writev+0x74/0xb0 fs/read_write.c:1323 do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline] do_fast_syscall_32+0x27b/0xdb3 arch/x86/entry/common.c:404 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fd7a39 Code: 00 00 00 89 d3 5b 5e 5f 5d c3 b8 80 96 98 00 eb c4 8b 04 24 c3 8b 1c 24 c3 8b 34 24 c3 8b 3c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f7f4f0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000092 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000240 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 28250: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:510 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3550 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:690 [inline] sctp_endpoint_new+0x79/0xb90 net/sctp/endpointola.c:133 sctp_init_sock+0xc2a/0x1360 net/sctp/socket.c:5089 inet6_create net/ipv6/af_inet6.c:253 [inline] inet6_create+0x9c0/0xf80 net/ipv6/af_inet6.c:107 __sock_create+0x3d8/0x730 net/socket.c:1418 sock_create net/socket.c:1469 [inline] __sys_socket+0x103/0x220 net/socket.c:1511 __do_sys_socket net/socket.c:1520 [inline] __se_sys_socket net/socket.c:1518 [inline] __ia32_sys_socket+0x73/0xb0 net/socket.c:1518 do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline] do_fast_syscall_32+0x27b/0xdb3 arch/x86/entry/common.c:404 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 Freed by task 28245: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] kasan_set_free_info mm/kasan/common.c:332 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:471 kasan_slab_free+0xe/0x10 mm/kasan/common.c:480 __cache_free mm/slab.c:3425 [inline] kfree+0x10a/0x2c0 mm/slab.c:3756 sctp_endpoint_destroy net/sctp/endpointola.c:219 [inline] sctp_endpoint_put+0x1a7/0x210 net/sctp/endpointola.c:235 sctp_endpoint_free+0x77/0x90 net/sctp/endpointola.c:182 sctp_destroy_sock+0x9f/0x3e0 net/sctp/socket.c:5142 sctp_v6_destroy_sock+0x16/0x30 net/sctp/socket.c:9523 sk_common_release+0x6b/0x340 net/core/sock.c:3172 sctp_close+0x4f6/0x880 net/sctp/socket.c:1537 inet_release+0xed/0x200 net/ipv4/af_inet.c:427 inet6_release+0x53/0x80 net/ipv6/af_inet6.c:470 __sock_release+0xce/0x280 net/socket.c:590 sock_close+0x1e/0x30 net/socket.c:1268 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 get_signal+0x2078/0x2500 kernel/signal.c:2528 do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_32_irqs_on arch/x86/entry/common.c:348 [inline] do_fast_syscall_32+0xb87/0xdb3 arch/x86/entry/common.c:404 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 The buggy address belongs to the object at ffff88808231c400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 152 bytes inside of 512-byte region [ffff88808231c400, ffff88808231c600) The buggy address belongs to the page: page:ffffea000208c700 refcount:1 mapcount:0 mapping:ffff8880aa400a80 index:0xffff88808231cc00 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002873c88 ffffea000238f708 ffff8880aa400a80 raw: ffff88808231cc00 ffff88808231c000 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808231c380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808231c400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88808231c480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88808231c500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808231c580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================