linux-kernel - [PATCH 1/4] ufs: validate maximum fast symlink size from superblock

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]

Date:	Wed, 31 Dec 2008 16:50:05 +0000
From:	"Duane Griffin" <duaneg@...da.com>
To:	Evgeniy Dushistov <dushistov@...l.ru>
Cc:	linux-kernel@...r.kernel.org, Duane Griffin <duaneg@...da.com>
Subject: [PATCH 1/4] ufs: validate maximum fast symlink size from superblock

The maximum fast symlink size is set in the superblock of certain types
of UFS filesystem. Before using it we need to check that it isn't longer
than the available space we have in the inode.

Signed-off-by: Duane Griffin <duaneg@...da.com>
---
 fs/ufs/super.c |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/fs/ufs/super.c b/fs/ufs/super.c
index e65212d..a959cdc 100644
--- a/fs/ufs/super.c
+++ b/fs/ufs/super.c
@@ -636,6 +636,7 @@ static int ufs_fill_super(struct super_block *sb, void *data, int silent)
 	unsigned block_size, super_block_size;
 	unsigned flags;
 	unsigned super_block_offset;
+	unsigned maxsymlen;
 	int ret = -EINVAL;
 
 	uspi = NULL;
@@ -1069,6 +1070,16 @@ magic_found:
 		uspi->s_maxsymlinklen =
 		    fs32_to_cpu(sb, usb3->fs_un2.fs_44.fs_maxsymlinklen);
 
+	if (uspi->fs_magic == UFS2_MAGIC)
+		maxsymlen = 2 * 4 * (UFS_NDADDR + UFS_NINDIR);
+	else
+		maxsymlen = 4 * (UFS_NDADDR + UFS_NINDIR);
+	if (uspi->s_maxsymlinklen > maxsymlen) {
+		printk(KERN_WARNING "ufs_read_super: excessive maximum fast "
+		       "symlink size (%u)\n", uspi->s_maxsymlinklen);
+		uspi->s_maxsymlinklen = maxsymlen;
+	}
+
 	inode = ufs_iget(sb, UFS_ROOTINO);
 	if (IS_ERR(inode)) {
 		ret = PTR_ERR(inode);
-- 
1.6.0.6

--
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/