The result from readlink is being used to index into the link name buffer without checking whether it is a valid length. If readlink returns an error this will fault or cause memory corruption. Cc: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxx> Cc: Dustin Kirkland <kirkland@xxxxxxxxxxxxx> Cc: ecryptfs-devel@xxxxxxxxxxxxxxxxxxx Signed-off-by: Duane Griffin <duaneg@xxxxxxxxx> Acked-by: Michael Halcrow <mhalcrow@xxxxxxxxxx> --- Unchanged from original version. fs/ecryptfs/inode.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 89209f0..5e78fc1 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -673,10 +673,11 @@ static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd) ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " "dentry->d_name.name = [%s]\n", dentry->d_name.name); rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); - buf[rc] = '\0'; set_fs(old_fs); if (rc < 0) goto out_free; + else + buf[rc] = '\0'; rc = 0; nd_set_link(nd, buf); goto out; -- 1.6.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
