Merge branch 'maint' into next

[tools/e2fsprogs.git] / lib / ext2fs / csum.c

diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c
index 607f74a..9f08c38 100644 (file)
--- a/lib/ext2fs/csum.c
+++ b/lib/ext2fs/csum.c
@@ -721,29 +721,23 @@ errcode_t ext2fs_inode_csum_set(ext2_filsys fs, ext2_ino_t inum,
 
 __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group)
 {
+       struct ext2_group_desc *desc = ext2fs_group_desc(fs, fs->group_desc,
+                                                        group);
+       size_t size = EXT2_DESC_SIZE(fs->super);
+       size_t offset;
        __u16 crc = 0;
-       struct ext2_group_desc *desc;
-       size_t size;
-
-       size = fs->super->s_desc_size;
-       if (size < EXT2_MIN_DESC_SIZE)
-               size = EXT2_MIN_DESC_SIZE;
-       if (size > sizeof(struct ext4_group_desc)) {
-               /* This should never happen, but cap it for safety's sake */
-               size = sizeof(struct ext4_group_desc);
-       }
-
-       desc = ext2fs_group_desc(fs, fs->group_desc, group);
-
 #ifdef WORDS_BIGENDIAN
        struct ext4_group_desc swabdesc;
+       size_t save_size = size;
+       const size_t ext4_bg_size = sizeof(struct ext4_group_desc);
+       struct ext2_group_desc *save_desc = desc;
 
        /* Have to swab back to little-endian to do the checksum */
+       if (size > ext4_bg_size)
+               size = ext4_bg_size;
        memcpy(&swabdesc, desc, size);
-       ext2fs_swap_group_desc2(fs,
-                               (struct ext2_group_desc *) &swabdesc);
+       ext2fs_swap_group_desc2(fs, (struct ext2_group_desc *) &swabdesc);
        desc = (struct ext2_group_desc *) &swabdesc;
-
        group = ext2fs_swab32(group);
 #endif
 
@@ -760,13 +754,18 @@ __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group)
                crc32 = ext2fs_crc32c_le(crc32, (unsigned char *)desc,
                                         size);
                desc->bg_checksum = old_crc;
-
+#ifdef WORDS_BIGENDIAN
+               if (save_size > ext4_bg_size)
+                       crc32 = ext2fs_crc32c_le(crc32,
+                                          (char *)save_desc + ext4_bg_size,
+                                          save_size - ext4_bg_size);
+#endif
                crc = crc32 & 0xFFFF;
                goto out;
        }
 
        /* old crc16 code */
-       size_t offset = offsetof(struct ext2_group_desc, bg_checksum);
+       offset = offsetof(struct ext2_group_desc, bg_checksum);
        crc = ext2fs_crc16(~0, fs->super->s_uuid,
                           sizeof(fs->super->s_uuid));
        crc = ext2fs_crc16(crc, &group, sizeof(group));
@@ -777,6 +776,16 @@ __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group)
                crc = ext2fs_crc16(crc, (char *)desc + offset,
                                   size - offset);
        }
+#ifdef WORDS_BIGENDIAN
+       /*
+        * If the size of the bg descriptor is greater than 64
+        * bytes, which is the size of the traditional ext4 bg
+        * descriptor, checksum the rest of the descriptor here
+        */
+       if (save_size > ext4_bg_size)
+               crc = ext2fs_crc16(crc, (char *)save_desc + ext4_bg_size,
+                                  save_size - ext4_bg_size);
+#endif
 
 out:
        return crc;
@@ -870,22 +879,22 @@ void print_csum(const char *msg, ext2_filsys fs, dgrp_t group)
 {
        __u16 crc1, crc2, crc3;
        dgrp_t swabgroup;
-       struct ext2_group_desc *desc;
-       size_t size;
+       struct ext2_group_desc *desc = ext2fs_group_desc(fs, fs->group_desc,
+                                                        group);
+       size_t size = EXT2_DESC_SIZE(fs->super);
        struct ext2_super_block *sb = fs->super;
        int offset = offsetof(struct ext2_group_desc, bg_checksum);
 #ifdef WORDS_BIGENDIAN
        struct ext4_group_desc swabdesc;
+       struct ext2_group_desc *save_desc = desc;
+       const size_t ext4_bg_size = sizeof(struct ext4_group_desc);
+       size_t save_size = size;
 #endif
 
-       desc = ext2fs_group_desc(fs, fs->group_desc, group);
-       size = fs->super->s_desc_size;
-       if (size < EXT2_MIN_DESC_SIZE)
-               size = EXT2_MIN_DESC_SIZE;
-       if (size > sizeof(struct ext4_group_desc))
-               size = sizeof(struct ext4_group_desc);
 #ifdef WORDS_BIGENDIAN
        /* Have to swab back to little-endian to do the checksum */
+       if (size > ext4_bg_size)
+               size = ext4_bg_size;
        memcpy(&swabdesc, desc, size);
        ext2fs_swap_group_desc2(fs, (struct ext2_group_desc *) &swabdesc);
        desc = (struct ext2_group_desc *) &swabdesc;
@@ -902,6 +911,11 @@ void print_csum(const char *msg, ext2_filsys fs, dgrp_t group)
        /* for checksum of struct ext4_group_desc do the rest...*/
        if (offset < size)
                crc3 = ext2fs_crc16(crc3, (char *)desc + offset, size - offset);
+#ifdef WORDS_BIGENDIAN
+       if (save_size > ext4_bg_size)
+               crc3 = ext2fs_crc16(crc3, (char *)save_desc + ext4_bg_size,
+                                   save_size - ext4_bg_size);
+#endif
 
        printf("%s UUID %s=%04x, grp %u=%04x: %04x=%04x\n",
               msg, e2p_uuid2str(sb->s_uuid), crc1, group, crc2, crc3,
@@ -921,6 +935,11 @@ int main(int argc, char **argv)
 
        memset(&param, 0, sizeof(param));
        ext2fs_blocks_count_set(&param, 32768);
+#if 0
+       param.s_feature_incompat |= EXT4_FEATURE_INCOMPAT_64BIT;
+       param.s_desc_size = 128;
+       csum_known = 0x5b6e;
+#endif
 
        retval = ext2fs_initialize("test fs", EXT2_FLAG_64BITS, &param,
                                   test_io_manager, &fs);