Merge tag 'squashfs-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next

Pull squashfs updates from Phillip Lougher:
 "Add an extra mount time sanity check, plus some code cleanups and bug
  fixes."

* tag 'squashfs-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next:
  Squashfs: add mount time sanity check for block_size and block_log match
  Squashfs: fix f_pos check in get_dir_index_using_offset
  Squashfs: get rid of obsolete definitions in header file
  Squashfs: remove redundant length initialisation in squashfs_lookup
  Squashfs: remove redundant length initialisation in squashfs_readdir
  Squashfs: update comment removing reference to zlib only
  Squashfs: use define instead of constant

5 files changed, 15 insertions, 24 deletions

diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c
index ed0eb2a921f4..fb50652e4e11 100644
--- a/fs/squashfs/block.c
+++ b/fs/squashfs/block.c
@@ -83,7 +83,8 @@ static struct buffer_head *get_block_length(struct super_block *sb,
  * filesystem), otherwise the length is obtained from the first two bytes of
  * the metadata block.  A bit in the length field indicates if the block
  * is stored uncompressed in the filesystem (usually because compression
- * generated a larger block - this does occasionally happen with zlib).
+ * generated a larger block - this does occasionally happen with compression
+ * algorithms).
  */
 int squashfs_read_data(struct super_block *sb, void **buffer, u64 index,
                         int length, u64 *next_index, int srclength, int pages)
diff --git a/fs/squashfs/dir.c b/fs/squashfs/dir.c
index 9dfe2ce0fb70..b381305c9a47 100644
--- a/fs/squashfs/dir.c
+++ b/fs/squashfs/dir.c
@@ -64,7 +64,7 @@ static int get_dir_index_using_offset(struct super_block *sb,
          * is offset by 3 because we invent "." and ".." entries which are
          * not actually stored in the directory.
          */
-        if (f_pos < 3)
+        if (f_pos <= 3)
                 return f_pos;
         f_pos -= 3;
 
@@ -105,7 +105,7 @@ static int squashfs_readdir(struct file *file, void *dirent, filldir_t filldir)
         struct inode *inode = file->f_dentry->d_inode;
         struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
         u64 block = squashfs_i(inode)->start + msblk->directory_table;
-        int offset = squashfs_i(inode)->offset, length = 0, dir_count, size,
+        int offset = squashfs_i(inode)->offset, length, dir_count, size,
                                 type, err;
         unsigned int inode_number;
         struct squashfs_dir_header dirh;
@@ -173,8 +173,7 @@ static int squashfs_readdir(struct file *file, void *dirent, filldir_t filldir)
 
                 dir_count = le32_to_cpu(dirh.count) + 1;
 
-                /* dir_count should never be larger than 256 */
-                if (dir_count > 256)
+                if (dir_count > SQUASHFS_DIR_COUNT)
                         goto failed_read;
 
                 while (dir_count--) {
diff --git a/fs/squashfs/namei.c b/fs/squashfs/namei.c
index 0682b38d7e31..abcc58f3c152 100644
--- a/fs/squashfs/namei.c
+++ b/fs/squashfs/namei.c
@@ -144,7 +144,7 @@ static struct dentry *squashfs_lookup(struct inode *dir, struct dentry *dentry,
         struct squashfs_dir_entry *dire;
         u64 block = squashfs_i(dir)->start + msblk->directory_table;
         int offset = squashfs_i(dir)->offset;
-        int err, length = 0, dir_count, size;
+        int err, length, dir_count, size;
 
         TRACE("Entered squashfs_lookup [%llx:%x]\n", block, offset);
 
@@ -177,8 +177,7 @@ static struct dentry *squashfs_lookup(struct inode *dir, struct dentry *dentry,
 
                 dir_count = le32_to_cpu(dirh.count) + 1;
 
-                /* dir_count should never be larger than 256 */
-                if (dir_count > 256)
+                if (dir_count > SQUASHFS_DIR_COUNT)
                         goto data_error;
 
                 while (dir_count--) {
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h
index e8e14645de9a..9e2349d07cb1 100644
--- a/fs/squashfs/squashfs_fs.h
+++ b/fs/squashfs/squashfs_fs.h
@@ -30,11 +30,6 @@
 
 /* size of metadata (inode and directory) blocks */
 #define SQUASHFS_METADATA_SIZE          8192
-#define SQUASHFS_METADATA_LOG           13
-
-/* default size of data blocks */
-#define SQUASHFS_FILE_SIZE              131072
-#define SQUASHFS_FILE_LOG               17
 
 /* default size of block device I/O */
 #ifdef CONFIG_SQUASHFS_4K_DEVBLK_SIZE
@@ -46,12 +41,12 @@
 #define SQUASHFS_FILE_MAX_SIZE          1048576
 #define SQUASHFS_FILE_MAX_LOG           20
 
-/* Max number of uids and gids */
-#define SQUASHFS_IDS                    65536
-
 /* Max length of filename (not 255) */
 #define SQUASHFS_NAME_LEN               256
 
+/* Max value for directory header count*/
+#define SQUASHFS_DIR_COUNT              256
+
 #define SQUASHFS_INVALID_FRAG           (0xffffffffU)
 #define SQUASHFS_INVALID_XATTR          (0xffffffffU)
 #define SQUASHFS_INVALID_BLK            (-1LL)
@@ -142,9 +137,6 @@
 #define SQUASHFS_MKINODE(A, B)          ((long long)(((long long) (A)\
                                         << 16) + (B)))
 
-/* Translate between VFS mode and squashfs mode */
-#define SQUASHFS_MODE(A)                ((A) & 0xfff)
-
 /* fragment and fragment table defines */
 #define SQUASHFS_FRAGMENT_BYTES(A)      \
                                 ((A) * sizeof(struct squashfs_fragment_entry))
@@ -215,11 +207,6 @@
 /* cached data constants for filesystem */
 #define SQUASHFS_CACHED_BLKS            8
 
-#define SQUASHFS_MAX_FILE_SIZE_LOG      64
-
-#define SQUASHFS_MAX_FILE_SIZE          (1LL << \
-                                        (SQUASHFS_MAX_FILE_SIZE_LOG - 2))
-
 /* meta index cache */
 #define SQUASHFS_META_INDEXES   (SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
 #define SQUASHFS_META_ENTRIES   127
diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
index 970b1167e7cb..29cd014ed3a1 100644
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -158,10 +158,15 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
                 goto failed_mount;
         }
 
+        /* Check block log for sanity */
         msblk->block_log = le16_to_cpu(sblk->block_log);
         if (msblk->block_log > SQUASHFS_FILE_MAX_LOG)
                 goto failed_mount;
 
+        /* Check that block_size and block_log match */
+        if (msblk->block_size != (1 << msblk->block_log))
+                goto failed_mount;
+
         /* Check the root inode for sanity */
         root_inode = le64_to_cpu(sblk->root_inode);
         if (SQUASHFS_INODE_OFFSET(root_inode) > SQUASHFS_METADATA_SIZE)