From mboxrd@z Thu Jan 1 00:00:00 1970 From: syzbot Subject: general protection fault in vsscanf Date: Tue, 10 Jul 2018 12:19:02 -0700 Message-ID: <000000000000bf0d390570aa008d@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes To: davem@davemloft.net, ericvh@gmail.com, linux-kernel@vger.kernel.org, lucho@ionkov.net, netdev@vger.kernel.org, rminnich@sandia.gov, syzkaller-bugs@googlegroups.com, v9fs-developer@lists.sourceforge.net Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 092150a25cb7 Merge branch 'for-linus' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1260ef34400000 kernel config: https://syzkaller.appspot.com/x/.config?x=25856fac4e580aa7 dashboard link: https://syzkaller.appspot.com/bug?extid=0ec640a6eebcf1c82417 compiler: gcc (GCC) 8.0.1 20180413 (experimental) userspace arch: i386 syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=14c2f50c400000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14fe4c58400000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+0ec640a6eebcf1c82417@syzkaller.appspotmail.com 9pnet: p9_fd_create_tcp (4481): problem connecting socket to 127.0.0.1 9pnet: p9_fd_create_tcp (4506): problem connecting socket to 127.0.0.1 kasan: CONFIG_KASAN_INLINE enabled kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN kasan: GPF could be caused by NULL-ptr deref or user memory access CPU: 1 PID: 4502 Comm: syz-executor518 Not tainted 4.18.0-rc4+ #42 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:vsscanf+0x3c1/0x2af0 lib/vsprintf.c:2966 Code: f9 44 89 ee bf 6e 00 00 00 e8 5b 82 eb f9 41 80 fd 6e 0f 84 ce 02 00 00 e8 7c 81 eb f9 4c 89 f0 4c 89 f2 48 c1 e8 03 83 e2 07 <42> 0f b6 04 38 38 d0 7f 08 84 c0 0f 85 e8 1c 00 00 45 0f b6 26 31 RSP: 0018:ffff8801bf93f0a0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffff888364c1 RCX: ffffffff87908a15 RDX: 0000000000000000 RSI: ffffffff87908a24 RDI: 0000000000000001 RBP: ffff8801bf93f270 R08: ffff8801b5e9a140 R09: ffff8801bf93f464 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff888364c1 R13: 0000000000000064 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8801daf00000(0063) knlGS:00000000f7efcb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f7f3dcc4 CR3: 00000001b6883000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sscanf+0xab/0xe0 lib/vsprintf.c:3172 valid_ipaddr4 net/9p/trans_fd.c:903 [inline] p9_fd_create_tcp+0x113/0x8a0 net/9p/trans_fd.c:943 p9_client_create+0x915/0x16c9 net/9p/client.c:1062 v9fs_session_init+0x21a/0x1a80 fs/9p/v9fs.c:400 v9fs_mount+0x7c/0x900 fs/9p/vfs_super.c:135 mount_fs+0xae/0x328 fs/super.c:1277 vfs_kern_mount.part.34+0xdc/0x4e0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:1027 [inline] do_new_mount fs/namespace.c:2518 [inline] do_mount+0x581/0x30e0 fs/namespace.c:2848 __do_compat_sys_mount fs/compat.c:125 [inline] __se_compat_sys_mount fs/compat.c:92 [inline] __ia32_compat_sys_mount+0x5d5/0x860 fs/compat.c:92 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f42cb9 Code: 55 08 8b 88 64 cd ff ff 8b 98 68 cd ff ff 89 c8 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 1c 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:00000000f7efc1ec EFLAGS: 00000296 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000200000c0 RDX: 0000000020000340 RSI: 0000000000000000 RDI: 0000000020000180 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: Dumping ftrace buffer: (ftrace buffer empty) general protection fault: 0000 [#2] SMP KASAN ---[ end trace 603612217fadf6c1 ]--- CPU: 0 PID: 4504 Comm: syz-executor518 Tainted: G D 4.18.0-rc4+ #42 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:vsscanf+0x3c1/0x2af0 lib/vsprintf.c:2966 RIP: 0010:vsscanf+0x3c1/0x2af0 lib/vsprintf.c:2966 Code: f9 44 89 ee bf 6e 00 00 00 e8 Code: 5b 82 eb f9 41 80 f9 fd 6e 0f 84 ce 02 44 00 00 e8 7c 81 eb 89 f9 4c 89 f0 4c 89 ee f2 48 c1 e8 03 83 bf e2 07 <42> 0f b6 04 6e 38 38 d0 7f 08 84 00 c0 0f 85 e8 1c 00 00 00 45 0f b6 26 31 RSP: 0018:ffff8801af7ff0a0 EFLAGS: 00010246 00 RAX: 0000000000000000 RBX: ffffffff888364c1 RCX: ffffffff87908a15 RDX: 0000000000000000 RSI: ffffffff87908a24 RDI: 0000000000000001 RBP: ffff8801af7ff270 R08: ffff8801b5e2a1c0 R09: ffff8801af7ff464 e8 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff888364c1 R13: 0000000000000064 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8801dae00000(0063) knlGS:00000000f7efcb40 5b CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000008090b10 CR3: 00000001b5f70000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 82 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: eb f9 41 80 sscanf+0xab/0xe0 lib/vsprintf.c:3172 fd 6e valid_ipaddr4 net/9p/trans_fd.c:903 [inline] p9_fd_create_tcp+0x113/0x8a0 net/9p/trans_fd.c:943 0f 84 ce 02 p9_client_create+0x915/0x16c9 net/9p/client.c:1062 00 00 e8 7c 81 eb v9fs_session_init+0x21a/0x1a80 fs/9p/v9fs.c:400 f9 4c 89 f0 4c v9fs_mount+0x7c/0x900 fs/9p/vfs_super.c:135 mount_fs+0xae/0x328 fs/super.c:1277 89 vfs_kern_mount.part.34+0xdc/0x4e0 fs/namespace.c:1037 f2 48 vfs_kern_mount fs/namespace.c:1027 [inline] do_new_mount fs/namespace.c:2518 [inline] do_mount+0x581/0x30e0 fs/namespace.c:2848 c1 e8 03 83 __do_compat_sys_mount fs/compat.c:125 [inline] __se_compat_sys_mount fs/compat.c:92 [inline] __ia32_compat_sys_mount+0x5d5/0x860 fs/compat.c:92 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397 e2 07 <42> 0f entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 b6 RIP: 0023:0xf7f42cb9 Code: 55 08 04 8b 88 64 cd ff ff 38 8b 98 68 cd ff ff 89 38 c8 85 d2 74 02 89 0a d0 5b 5d c3 8b 04 24 7f c3 8b 1c 24 c3 51 52 08 55 89 e5 0f 34 cd 84 80 <5d> 5a 59 c3 90 90 c0 90 90 eb 0d 90 90 90 0f 90 90 90 90 90 90 85 90 90 90 RSP: 002b:00000000f7efc1ec EFLAGS: 00000296 ORIG_RAX: 0000000000000015 e8 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000200000c0 RDX: 0000000020000340 RSI: 0000000000000000 RDI: 0000000020000180 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 1c R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: 00 Dumping ftrace buffer: (ftrace buffer empty) ---[ end trace 603612217fadf6c2 ]--- 00 RIP: 0010:vsscanf+0x3c1/0x2af0 lib/vsprintf.c:2966 Code: 45 f9 44 89 ee bf 0f 6e 00 b6 00 00 26 e8 31 5b 82 eb f9 RSP: 0018:ffff8801bf93f0a0 EFLAGS: 00010246 41 80 fd 6e RAX: 0000000000000000 RBX: ffffffff888364c1 RCX: ffffffff87908a15 0f 84 RDX: 0000000000000000 RSI: ffffffff87908a24 RDI: 0000000000000001 ce 02 RBP: ffff8801bf93f270 R08: ffff8801b5e9a140 R09: ffff8801bf93f464 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff888364c1 00 00 R13: 0000000000000064 R14: 0000000000000000 R15: dffffc0000000000 e8 7c FS: 0000000000000000(0000) GS:ffff8801daf00000(0063) knlGS:00000000f7efcb40 81 eb CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 f9 4c CR2: 00000000f7f3dcc4 CR3: 00000001b6883000 CR4: 00000000001406e0 89 f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 4c 89 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 f2 48 --- This bug is generated by a bot. 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