linux-kernel - [PATCH] cifs: fix length calculation for converted unicode readdir names

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1265393640-7296-1-git-send-email-jlayton@redhat.com>
Date:	Fri,  5 Feb 2010 13:14:00 -0500
From:	Jeff Layton <jlayton@...hat.com>
To:	smfrench@...il.com
Cc:	linux-kernel@...r.kernel.org, linux-cifs-client@...ts.samba.org,
	linux-fsdevel@...r.kernel.org, stable@...nel.org
Subject: [PATCH] cifs: fix length calculation for converted unicode readdir names

cifs_from_ucs2 returns the length of the converted name, including the
length of the NULL terminator. We don't want to include the NULL
terminator in the dentry name length however since that'll throw off the
hash calculation for the dentry cache.

I believe that this is the root cause of several problems that have
cropped up recently that seem to be papered over with the "noserverino"
mount option. More confirmation of that would be good, but this is
clearly a bug and it fixes at least one reproducible problem that
was reported.

This patch fixes at least this reproducer in this kernel.org bug:

    http://bugzilla.kernel.org/show_bug.cgi?id=15088#c12

Reported-by: Bjorn Tore Sund <bjorn.sund@...uib.no>
Signed-off-by: Jeff Layton <jlayton@...hat.com>
Cc: stable@...nel.org
---
 fs/cifs/readdir.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index f84062f..f5618f8 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -666,6 +666,7 @@ static int cifs_get_name_from_search_buf(struct qstr *pqst,
 					   min(len, max_len), nlt,
 					   cifs_sb->mnt_cifs_flags &
 						CIFS_MOUNT_MAP_SPECIAL_CHR);
+		pqst->len -= nls_nullsize(nlt);
 	} else {
 		pqst->name = filename;
 		pqst->len = len;
-- 
1.6.6

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/