ext4: validate that metadata blocks do not overlap superblock

[pandora-kernel.git] / fs / ext4 / super.c

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 52b8ac7..7266a2e 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2097,6 +2097,7 @@ int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
 
 /* Called at mount-time, super-block is locked */
 static int ext4_check_descriptors(struct super_block *sb,
+                                 ext4_fsblk_t sb_block,
                                  ext4_group_t *first_not_zeroed)
 {
        struct ext4_sb_info *sbi = EXT4_SB(sb);
@@ -2127,6 +2128,11 @@ static int ext4_check_descriptors(struct super_block *sb,
                        grp = i;
 
                block_bitmap = ext4_block_bitmap(sb, gdp);
+               if (block_bitmap == sb_block) {
+                       ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
+                                "Block bitmap for group %u overlaps "
+                                "superblock", i);
+               }
                if (block_bitmap < first_block || block_bitmap > last_block) {
                        ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
                               "Block bitmap for group %u not in group "
@@ -2134,6 +2140,11 @@ static int ext4_check_descriptors(struct super_block *sb,
                        return 0;
                }
                inode_bitmap = ext4_inode_bitmap(sb, gdp);
+               if (inode_bitmap == sb_block) {
+                       ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
+                                "Inode bitmap for group %u overlaps "
+                                "superblock", i);
+               }
                if (inode_bitmap < first_block || inode_bitmap > last_block) {
                        ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
                               "Inode bitmap for group %u not in group "
@@ -2141,6 +2152,11 @@ static int ext4_check_descriptors(struct super_block *sb,
                        return 0;
                }
                inode_table = ext4_inode_table(sb, gdp);
+               if (inode_table == sb_block) {
+                       ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
+                                "Inode table for group %u overlaps "
+                                "superblock", i);
+               }
                if (inode_table < first_block ||
                    inode_table + sbi->s_itb_per_group - 1 > last_block) {
                        ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
@@ -2246,6 +2262,16 @@ static void ext4_orphan_cleanup(struct super_block *sb,
        while (es->s_last_orphan) {
                struct inode *inode;
 
+               /*
+                * We may have encountered an error during cleanup; if
+                * so, skip the rest.
+                */
+               if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
+                       jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
+                       es->s_last_orphan = 0;
+                       break;
+               }
+
                inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
                if (IS_ERR(inode)) {
                        es->s_last_orphan = 0;
@@ -3429,6 +3455,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                goto failed_mount;
        }
 
+       if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
+               ext4_msg(sb, KERN_ERR,
+                        "Number of reserved GDT blocks insanely large: %d",
+                        le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
+               goto failed_mount;
+       }
+
        if (sb->s_blocksize != blocksize) {
                /* Validate the filesystem blocksize */
                if (!sb_set_blocksize(sb, blocksize)) {
@@ -3657,7 +3690,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                        goto failed_mount2;
                }
        }
-       if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
+       if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
                ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
                goto failed_mount2;
        }