From: Eric Sandeen Date: Thu, 9 Oct 2008 15:15:52 +0000 (-0400) Subject: ext4: Avoid printk floods in the face of directory corruption X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=9d9f177572d9e4eba0f2e18523b44f90dd51fe74;p=openwrt%2Fstaging%2Fblogic.git ext4: Avoid printk floods in the face of directory corruption Note: some people thinks this represents a security bug, since it might make the system go away while it is printing a large number of console messages, especially if a serial console is involved. Hence, it has been assigned CVE-2008-3528, but it requires that the attacker either has physical access to your machine to insert a USB disk with a corrupted filesystem image (at which point why not just hit the power button), or is otherwise able to convince the system administrator to mount an arbitrary filesystem image (at which point why not just include a setuid shell or world-writable hard disk device file or some such). Me, I think they're just being silly. --tytso Signed-off-by: Eric Sandeen Signed-off-by: "Theodore Ts'o" Cc: linux-ext4@vger.kernel.org Cc: Eugene Teo --- diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index d40da316921d..3ca6a2b7632d 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -102,6 +102,7 @@ static int ext4_readdir(struct file *filp, int err; struct inode *inode = filp->f_path.dentry->d_inode; int ret = 0; + int dir_has_error = 0; sb = inode->i_sb; @@ -148,9 +149,13 @@ static int ext4_readdir(struct file *filp, * of recovering data when there's a bad sector */ if (!bh) { - ext4_error(sb, "ext4_readdir", - "directory #%lu contains a hole at offset %lu", - inode->i_ino, (unsigned long)filp->f_pos); + if (!dir_has_error) { + ext4_error(sb, __func__, "directory #%lu " + "contains a hole at offset %Lu", + inode->i_ino, + (unsigned long long) filp->f_pos); + dir_has_error = 1; + } /* corrupt size? Maybe no more blocks to read */ if (filp->f_pos > inode->i_blocks << 9) break;