Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932067AbYCUWvu (ORCPT ); Fri, 21 Mar 2008 18:51:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762870AbYCUWqt (ORCPT ); Fri, 21 Mar 2008 18:46:49 -0400 Received: from 216-99-217-87.dsl.aracnet.com ([216.99.217.87]:58934 "EHLO sous-sol.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762861AbYCUWqs (ORCPT ); Fri, 21 Mar 2008 18:46:48 -0400 Message-Id: <20080321224444.477482247@sous-sol.org> References: <20080321224250.144333319@sous-sol.org> User-Agent: quilt/0.46-1 Date: Fri, 21 Mar 2008 15:43:54 -0700 From: Chris Wright To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, "J. Bruce Fields" , Lukas Hejtmanek , Greg Kroah-Hartman Subject: [patch 64/76] nfsd: fix oops on access from high-numbered ports Content-Disposition: inline; filename=nfsd-fix-oops-on-access-from-high-numbered-ports.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2121 Lines: 62 -stable review patch. If anyone has any objections, please let us know. --------------------- From: J. Bruce Fields This bug was always here, but before my commit 6fa02839bf9412e18e77 ("recheck for secure ports in fh_verify"), it could only be triggered by failure of a kmalloc(). After that commit it could be triggered by a client making a request from a non-reserved port for access to an export marked "secure". (Exports are "secure" by default.) The result is a struct svc_export with a reference count one too low, resulting in likely oopses next time the export is accessed. The reference counting here is not straightforward; a later patch will clean up fh_verify(). Thanks to Lukas Hejtmanek for the bug report and followup. Signed-off-by: J. Bruce Fields Cc: Lukas Hejtmanek Signed-off-by: Linus Torvalds Signed-off-by: Chris Wright Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfsfh.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/nfsd/nfsfh.c +++ b/fs/nfsd/nfsfh.c @@ -231,6 +231,7 @@ fh_verify(struct svc_rqst *rqstp, struct fhp->fh_dentry = dentry; fhp->fh_export = exp; nfsd_nr_verified++; + cache_get(&exp->h); } else { /* * just rechecking permissions @@ -240,6 +241,7 @@ fh_verify(struct svc_rqst *rqstp, struct dprintk("nfsd: fh_verify - just checking\n"); dentry = fhp->fh_dentry; exp = fhp->fh_export; + cache_get(&exp->h); /* * Set user creds for this exportpoint; necessary even * in the "just checking" case because this may be a @@ -251,8 +253,6 @@ fh_verify(struct svc_rqst *rqstp, struct if (error) goto out; } - cache_get(&exp->h); - error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type); if (error) -- -- 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/