Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759946AbZDCHXX (ORCPT ); Fri, 3 Apr 2009 03:23:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751334AbZDCHXO (ORCPT ); Fri, 3 Apr 2009 03:23:14 -0400 Received: from courier.cs.helsinki.fi ([128.214.9.1]:36650 "EHLO mail.cs.helsinki.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751188AbZDCHXN (ORCPT ); Fri, 3 Apr 2009 03:23:13 -0400 Subject: Re: [PATCH] nfs: fix nfs_parse_mount_options() double kfree() From: Pekka Enberg To: Ingo Molnar Cc: Yinghai Lu , David Miller , "linux-kernel@vger.kernel.org" , Trond Myklebust , chuck.lever@oracle.com, Tom Talpey In-Reply-To: <20090403071638.GB14498@elte.hu> References: <86802c440904021512o2405ffa2gcbe057b9f81d5a46@mail.gmail.com> <20090402222106.GC9239@elte.hu> <49D56415.1080402@kernel.org> <84144f020904022252v2dbc18f5o35cc9737bf6d146d@mail.gmail.com> <20090403071638.GB14498@elte.hu> Date: Fri, 03 Apr 2009 10:23:09 +0300 Message-Id: <1238743389.4852.12.camel@penberg-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 7bit X-Mailer: Evolution 2.22.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4841 Lines: 85 On Fri, 2009-04-03 at 09:16 +0200, Ingo Molnar wrote: > Impact: fix crash > > Yinghai Lu reported the following crash: > > > mpk12-3214-189-158:~ # sh x > > [ 63.198629] ------------[ cut here ]------------ > > [ 63.202589] kernel BUG at mm/slub.c:2753! > > [ 63.202589] invalid opcode: 0000 [#1] SMP > > [ 63.202589] last sysfs file: /sys/devices/virtual/net/sit0/type > > [ 63.202589] CPU 0 > > [ 63.202589] Modules linked in: > > [ 63.202589] Pid: 10027, comm: mount.nfs Not tainted 2.6.29-07100-g833bb30 #21 Sun Fire X4440 > > [ 63.202589] RIP: 0010:[] [] kfree+0x5a/0xcd > > [ 63.202589] RSP: 0018:ffff882042ceb9f8 EFLAGS: 00010246 > > [ 63.202589] RAX: 0200000000000000 RBX: 0000000000000005 RCX: ffffffff80a7dc1f > > [ 63.202589] RDX: ffffe20000000000 RSI: ffffc2000000f470 RDI: ffffe2001c018950 > > [ 63.202589] RBP: ffff882042ceba18 R08: 0000000000000000 R09: ffffffff811019c0 > > [ 63.202589] R10: 000000004262ce02 R11: ffff882042ceba18 R12: ffff880800706475 > > [ 63.202589] R13: ffff882042886000 R14: ffff882042cebbd8 R15: ffff882042cebbf0 > > [ 63.202589] FS: 00007fac729ed6f0(0000) GS:ffffc20000000000(0000) knlGS:0000000000000000 > > [ 63.202589] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > > [ 63.202589] CR2: 00007fac72c12000 CR3: 0000001841cbb000 CR4: 00000000000006e0 > > [ 63.202589] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > [ 63.202589] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > > [ 63.202589] Process mount.nfs (pid: 10027, threadinfo ffff882042cea000, task ffff8820434dc290) > > [ 63.202589] Stack: > > [ 63.202589] ffff882042ceba18 000000004262ce02 0000000000000005 ffff882042886028 > > [ 63.202589] ffff882042ceba58 ffffffff80a7dc1f 000000004262ce02 ffff882042886000 > > [ 63.202589] 000000004262ce02 ffff882042886000 ffffffff80a7b4a6 ffff882042c9ee18 > > [ 63.202589] Call Trace: > > [ 63.202589] [] xs_destroy+0x67/0xac > > [ 63.202589] [] ? xprt_destroy+0x0/0xa7 > > [ 63.202589] [] xprt_destroy+0x8c/0xa7 > > [ 63.202589] [] ? put_rpccred+0x112/0x131 > > [ 63.202589] [] kref_put+0x65/0x87 > > [ 63.202589] [] ? rpc_free_client+0x0/0xf9 > > [ 63.202589] [] xprt_put+0x23/0x39 > > [ 63.202589] [] rpc_free_client+0xd1/0xf9 > > [ 63.202589] [] ? unx_destroy+0x3c/0x57 > > [ 63.202589] [] kref_put+0x65/0x87 > > [ 63.202589] [] ? rpc_free_auth+0x0/0x69 > > [ 63.202589] [] rpc_free_auth+0x4e/0x69 > > [ 63.202589] [] ? __wake_up+0x52/0x75 > > [ 63.202589] [] kref_put+0x65/0x87 > > [ 63.202589] [] rpc_release_client+0x64/0x7f > > [ 63.202589] [] ? rpc_put_task+0xb0/0xcb > > [ 63.202589] [] rpc_shutdown_client+0xd5/0xf8 > > [ 63.202589] [] ? rpc_call_sync+0x63/0x80 > > [ 63.202589] [] nfs_mount+0x11f/0x1bf > > [ 63.202589] [] nfs_get_sb+0x4ac/0x82a > > [ 63.202589] [] vfs_kern_mount+0x61/0xbf > > [ 63.202589] [] ? get_fs_type+0x58/0xc5 > > [ 63.202589] [] do_kern_mount+0x56/0x108 > > [ 63.202589] [] do_mount+0x729/0x788 > > [ 63.202589] [] ? copy_mount_options+0xdf/0x155 > > [ 63.202589] [] sys_mount+0x98/0xf8 > > [ 63.202589] [] system_call_fastpath+0x16/0x1b > > [ 63.202589] Code: 0c 48 ba 00 00 00 00 00 e2 ff ff 48 6b c0 38 48 8d 3c 10 48 8b 07 f6 c4 40 74 04 48 8b 7f 10 48 8b 07 84 c0 78 10 f6 c4 60 75 04 <0f> 0b eb fe e8 90 75 fd ff eb 4c 48 8b 4d 08 4c 8b 4f 10 9c 5b > > [ 63.202589] RIP [] kfree+0x5a/0xcd > > [ 63.202589] RSP > > [ 63.524555] ---[ end trace cd0d38e02ad11d61 ]--- > > Pekka observed that a bogus pointer was passed to kfree(). > > This commit: > > a67d18f: NFS: load the rpc/rdma transport module automatically > > Moved a kfree() of the options strings in nfs_parse_mount_options() > inadvertently and introduced a double kfree(). Fix it. > > Reported-by: Yinghai Lu > Analyzed-by: Pekka Enberg > Signed-off-by: Ingo Molnar Looks good! Reviewed-by: Pekka Enberg -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/