On Sat, Oct 27, 2018 at 1:38 AM syzbot <syzbot+5da0d0a72a9e7d791748@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following crash on: > > HEAD commit: bd6bf7c10484 Merge tag 'pci-v4.20-changes' of git://git.ke.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=16fd6bcb400000 > kernel config: https://syzkaller.appspot.com/x/.config?x=2dd8629d56664133 > dashboard link: https://syzkaller.appspot.com/bug?extid=5da0d0a72a9e7d791748 > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16b3ea33400000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f9f1bd400000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+5da0d0a72a9e7d791748@xxxxxxxxxxxxxxxxxxxxxxxxx > > ================================================================== > BUG: KASAN: slab-out-of-bounds in sctp_getsockopt_pr_streamstatus > net/sctp/socket.c:7174 [inline] Forgot to change to use "&" in sctp_getsockopt_pr_streamstatus() in "sctp: get pr_assoc and pr_stream all status with SCTP_PR_SCTP_ALL instead" @@ -7158,7 +7158,7 @@ static int sctp_getsockopt_pr_streamstatus(struct sock *sk, int len, goto out; } - if (policy == SCTP_PR_SCTP_ALL) { + if (policy & SCTP_PR_SCTP_ALL) { > BUG: KASAN: slab-out-of-bounds in sctp_getsockopt+0x7516/0x7cc2 > net/sctp/socket.c:7582 > Read of size 8 at addr ffff8801d89f0968 by task syz-executor278/5330 > > CPU: 1 PID: 5330 Comm: syz-executor278 Not tainted 4.19.0+ #303 > 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 > __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 > sctp_getsockopt_pr_streamstatus net/sctp/socket.c:7174 [inline] > sctp_getsockopt+0x7516/0x7cc2 net/sctp/socket.c:7582 > sock_common_getsockopt+0x9a/0xe0 net/core/sock.c:2937 > __sys_getsockopt+0x1ad/0x390 net/socket.c:1939 > __do_sys_getsockopt net/socket.c:1950 [inline] > __se_sys_getsockopt net/socket.c:1947 [inline] > __x64_sys_getsockopt+0xbe/0x150 net/socket.c:1947 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x445789 > Code: e8 6c b6 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007effdb293db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 > RAX: ffffffffffffffda RBX: 00000000006dac48 RCX: 0000000000445789 > RDX: 0000000000000074 RSI: 0000000000000084 RDI: 0000000000000003 > RBP: 00000000006dac40 R08: 0000000020000040 R09: 0000000000000000 > R10: 0000000020000080 R11: 0000000000000246 R12: 00000000006dac4c > R13: 00007ffcfc408c6f R14: 00007effdb2949c0 R15: 00000000006dad2c > > Allocated by task 5329: > 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:513 [inline] > kzalloc include/linux/slab.h:707 [inline] > sctp_stream_init_ext+0x4f/0xf0 net/sctp/stream.c:237 > sctp_sendmsg_to_asoc+0x1308/0x1a20 net/sctp/socket.c:1896 > sctp_sendmsg+0x13c2/0x1da0 net/sctp/socket.c:2113 > inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 > sock_sendmsg_nosec net/socket.c:621 [inline] > sock_sendmsg+0xd5/0x120 net/socket.c:631 > __sys_sendto+0x3d7/0x670 net/socket.c:1788 > __do_sys_sendto net/socket.c:1800 [inline] > __se_sys_sendto net/socket.c:1796 [inline] > __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1796 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > Freed by task 3223: > save_stack+0x43/0xd0 mm/kasan/kasan.c:448 > 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:3813 > kzfree+0x28/0x30 mm/slab_common.c:1543 > aa_free_file_ctx security/apparmor/include/file.h:76 [inline] > apparmor_file_free_security+0x133/0x1a0 security/apparmor/lsm.c:448 > security_file_free+0x4a/0x80 security/security.c:900 > file_free fs/file_table.c:54 [inline] > __fput+0x4e8/0xa30 fs/file_table.c:294 > ____fput+0x15/0x20 fs/file_table.c:309 > task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 > tracehook_notify_resume include/linux/tracehook.h:188 [inline] > exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 > prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] > syscall_return_slowpath arch/x86/entry/common.c:268 [inline] > do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > The buggy address belongs to the object at ffff8801d89f0900 > which belongs to the cache kmalloc-96 of size 96 > The buggy address is located 8 bytes to the right of > 96-byte region [ffff8801d89f0900, ffff8801d89f0960) > The buggy address belongs to the page: > page:ffffea0007627c00 count:1 mapcount:0 mapping:ffff8801da8004c0 index:0x0 > flags: 0x2fffc0000000100(slab) > raw: 02fffc0000000100 ffffea0007646748 ffffea0007613488 ffff8801da8004c0 > raw: 0000000000000000 ffff8801d89f0000 0000000100000020 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8801d89f0800: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > ffff8801d89f0880: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > > ffff8801d89f0900: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc > ^ > ffff8801d89f0980: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > ffff8801d89f0a00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > ================================================================== > > > --- > This bug is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. See: > https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with > syzbot. > syzbot can test patches for this bug, for details see: > https://goo.gl/tpsmEJ#testing-patches
