From mboxrd@z Thu Jan 1 00:00:00 1970 From: syzbot Subject: Re: KMSAN: uninit-value in p9_client_rpc Date: Thu, 12 Jul 2018 02:24:01 -0700 Message-ID: <00000000000077da4b0570c9eccc@google.com> References: <000000000000c541110570a978a4@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: In-Reply-To: <000000000000c541110570a978a4@google.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org syzbot has found a reproducer for the following crash on: HEAD commit: b64f7ec04e12 kmsan: implement kmsan_memmove_shadow() and k.. git tree: https://github.com/google/kmsan.git/master console output: https://syzkaller.appspot.com/x/log.txt?x=12f6791c400000 kernel config: https://syzkaller.appspot.com/x/.config?x=93d57043084eee38 dashboard link: https://syzkaller.appspot.com/bug?extid=4de40388f584432bf004 compiler: clang version 7.0.0 (trunk 334104) syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=147c36dc400000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14e87044400000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+4de40388f584432bf004@syzkaller.appspotmail.com FS-Cache: O-key=[10] '34323934373135343132' FS-Cache: N-cookie c=(____ptrval____) [p=(____ptrval____) fl=2 nc=0 na=1] FS-Cache: N-cookie d=(____ptrval____) n=(____ptrval____) FS-Cache: N-key=[10] '34323934373135343132' ================================================================== BUG: KMSAN: uninit-value in p9_client_rpc+0x194c/0x1dc0 net/9p/client.c:818 CPU: 1 PID: 4620 Comm: syz-executor262 Not tainted 4.18.0-rc4+ #24 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+0x185/0x1e0 lib/dump_stack.c:113 kmsan_report+0x195/0x2c0 mm/kmsan/kmsan.c:1092 __msan_warning_32+0x7d/0xe0 mm/kmsan/kmsan_instr.c:640 p9_client_rpc+0x194c/0x1dc0 net/9p/client.c:818 p9_client_attach+0x35b/0xc30 net/9p/client.c:1147 v9fs_session_init+0x24b9/0x2970 fs/9p/v9fs.c:449 v9fs_mount+0x107/0x11b0 fs/9p/vfs_super.c:135 mount_fs+0x29b/0x780 fs/super.c:1277 vfs_kern_mount+0x222/0x990 fs/namespace.c:1037 do_new_mount fs/namespace.c:2518 [inline] do_mount+0xd30/0x5310 fs/namespace.c:2848 ksys_mount+0x32e/0x3d0 fs/namespace.c:3064 __do_sys_mount fs/namespace.c:3078 [inline] __se_sys_mount fs/namespace.c:3075 [inline] __x64_sys_mount+0x157/0x1c0 fs/namespace.c:3075 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x445f79 Code: e8 cc e6 ff ff 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 3b 0d fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffb83104da8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000006dbc3c RCX: 0000000000445f79 RDX: 0000000020000180 RSI: 00000000200000c0 RDI: 0000000000000000 RBP: 00000000006dbc38 R08: 00000000200001c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0030656c69662f2e R13: 64663d736e617274 R14: 7974697275636573 R15: 0000000000000001 Local variable description: ----ecode.i@p9_client_rpc Variable was created at: p9_client_rpc+0x183/0x1dc0 net/9p/client.c:750 p9_client_attach+0x35b/0xc30 net/9p/client.c:1147 ==================================================================