Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:51946 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750974Ab0HQKL2 (ORCPT ); Tue, 17 Aug 2010 06:11:28 -0400 Message-ID: <4C6A5FF1.3070209@cn.fujitsu.com> Date: Tue, 17 Aug 2010 18:09:53 +0800 From: Bian Naimeng To: Adam Lackorzynski CC: linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, Trond Myklebust Subject: Re: 2.6.35.2: NFS related Oops References: <20100816215056.GA5376@os.inf.tu-dresden.de> In-Reply-To: <20100816215056.GA5376@os.inf.tu-dresden.de> Content-Type: text/plain; charset=Shift_JIS Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 > Hi, > > with 2.6.35.2 I'm getting this reproducible Oops: > Please try to apply the followed patch. ---- We we open a positive file just with O_EXCL but no O_CREAT, may cause kernel crash. Signed-off-by: Bian Naimeng --- fs/nfs/dir.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 29539ce..1a672dd 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1100,7 +1100,7 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd) goto no_open_dput; openflags = nd->intent.open.flags; /* We cannot do exclusive creation on a positive dentry */ - if ((openflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL)) + if (openflags & O_EXCL) goto no_open_dput; /* We can't create new files, or truncate existing ones here */ openflags &= ~(O_CREAT|O_TRUNC); -- 1.7.0 > [ 110.825396] BUG: unable to handle kernel NULL pointer dereference at (null) > [ 110.828638] IP: [] encode_attrs+0x1a/0x2a4 > [ 110.828638] PGD be89f067 PUD bf18f067 PMD 0 > [ 110.828638] Oops: 0000 [#1] SMP > [ 110.828638] last sysfs file: /sys/class/net/lo/operstate > [ 110.828638] CPU 2 > [ 110.828638] Modules linked in: rtc_cmos rtc_core rtc_lib amd64_edac_mod i2c_amd756 edac_core i2c_core dm_mirror dm_region_hash dm_log dm_snapshot sg sr_mod usb_storage ohci_hcd mptspi tg3 mptscsih mptbase usbcore nls_base [last unloaded: scsi_wait_scan] > [ 110.828638] > [ 110.828638] Pid: 11264, comm: setchecksum Not tainted 2.6.35.2 #1 > [ 110.828638] RIP: 0010:[] [] encode_attrs+0x1a/0x2a4 > [ 110.828638] RSP: 0000:ffff88003bf5b878 EFLAGS: 00010296 > [ 110.828638] RAX: ffff8800bddb48a8 RBX: ffff88003bf5bb18 RCX: 0000000000000000 > [ 110.828638] RDX: ffff8800be258800 RSI: 0000000000000000 RDI: ffff88003bf5b9f8 > [ 110.828638] RBP: 0000000000000000 R08: ffff8800bddb48a8 R09: 0000000000000004 > [ 110.828638] R10: 0000000000000003 R11: ffff8800be779000 R12: ffff8800be258800 > [ 110.828638] R13: ffff88003bf5b9f8 R14: ffff88003bf5bb20 R15: ffff8800be258800 > [ 110.828638] FS: 0000000000000000(0000) GS:ffff880041e00000(0063) knlGS:00000000556bd6b0 > [ 110.828638] CS: 0010 DS: 002b ES: 002b CR0: 000000008005003b > [ 110.828638] CR2: 0000000000000000 CR3: 00000000be8ef000 CR4: 00000000000006e0 > [ 110.828638] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 110.828638] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > [ 110.828638] Process setchecksum (pid: 11264, threadinfo ffff88003bf5a000, task ffff88003f232210) > [ 110.828638] Stack: > [ 110.828638] 0000000000000000 ffff8800bfbcf920 0000000000000000 0000000000000ffe > [ 110.828638] <0> 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > [ 110.828638] <0> 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > [ 110.828638] Call Trace: > [ 110.828638] [] ? nfs4_xdr_enc_setattr+0x90/0xb4 > [ 110.828638] [] ? call_transmit+0x1c3/0x24a > [ 110.828638] [] ? __rpc_execute+0x78/0x22a > [ 110.828638] [] ? rpc_run_task+0x21/0x2b > [ 110.828638] [] ? rpc_call_sync+0x3d/0x5d > [ 110.828638] [] ? _nfs4_do_setattr+0x11b/0x147 > [ 110.828638] [] ? nfs_init_locked+0x0/0x32 > [ 110.828638] [] ? ifind+0x4e/0x90 > [ 110.828638] [] ? nfs4_do_setattr+0x4b/0x6e > [ 110.828638] [] ? nfs4_do_open+0x291/0x3a6 > [ 110.828638] [] ? nfs4_open_revalidate+0x63/0x14a > [ 110.828638] [] ? nfs_open_revalidate+0xd7/0x161 > [ 110.828638] [] ? do_lookup+0x1a4/0x201 > [ 110.828638] [] ? link_path_walk+0x6a/0x9d5 > [ 110.828638] [] ? do_last+0x17b/0x58e > [ 110.828638] [] ? do_filp_open+0x1bd/0x56e > [ 110.828638] [] ? _atomic_dec_and_lock+0x30/0x48 > [ 110.828638] [] ? dput+0x37/0x152 > [ 110.828638] [] ? alloc_fd+0x69/0x10a > [ 110.828638] [] ? do_sys_open+0x56/0x100 > [ 110.828638] [] ? ia32_sysret+0x0/0x5 > [ 110.828638] Code: 83 f1 01 e8 f5 ca ff ff 48 83 c4 50 5b 5d 41 5c c3 41 57 41 56 41 55 49 89 fd 41 54 49 89 d4 55 48 89 f5 53 48 81 ec 18 01 00 00 <8b> 06 89 c2 83 e2 08 83 fa 01 19 db 83 e3 f8 83 c3 18 a8 01 8d > [ 110.828638] RIP [] encode_attrs+0x1a/0x2a4 > [ 110.828638] RSP > [ 110.828638] CR2: 0000000000000000 > [ 112.840396] ---[ end trace 95282e83fd77358f ]--- > > > Looks like arg->iap in encode_setattr() in nfs4xdr.c is 0. > > > > Adam -- Regards Bian Naimeng