From: Lukas Czerner Date: Mon, 9 Apr 2018 15:58:15 +0000 (-0400) Subject: e2image: fix metadata image handling on big endian systems X-Git-Tag: v1.44.2~10 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bfc1856029ff6851845de27114fea899bbdbccbe;p=thirdparty%2Fe2fsprogs.git e2image: fix metadata image handling on big endian systems Currently e2image metadata image handling and creating is completely broken on big endian systems. It just does not care about endianness at all. This was uncovered With addition of i_bitmaps test, which is the first test that actually tests e2image metadata image. Fix it by making sure that all on-disk metadata that we write and read to/from the metadata image is properly converted. Signed-off-by: Lukas Czerner Signed-off-by: Theodore Ts'o --- diff --git a/lib/ext2fs/imager.c b/lib/ext2fs/imager.c index efb85b947..7fd06f743 100644 --- a/lib/ext2fs/imager.c +++ b/lib/ext2fs/imager.c @@ -195,6 +195,11 @@ errcode_t ext2fs_image_super_write(ext2_filsys fs, int fd, char *buf, *cp; ssize_t actual; errcode_t retval; +#ifdef WORDS_BIGENDIAN + unsigned int groups_per_block; + struct ext2_group_desc *gdp; + int j; +#endif buf = malloc(fs->blocksize); if (!buf) @@ -204,7 +209,17 @@ errcode_t ext2fs_image_super_write(ext2_filsys fs, int fd, * Write out the superblock */ memset(buf, 0, fs->blocksize); +#ifdef WORDS_BIGENDIAN + /* + * We're writing out superblock so let's convert + * it to little endian and then back if needed + */ + ext2fs_swap_super(fs->super); memcpy(buf, fs->super, SUPERBLOCK_SIZE); + ext2fs_swap_super(fs->super); +#else + memcpy(buf, fs->super, SUPERBLOCK_SIZE); +#endif actual = write(fd, buf, fs->blocksize); if (actual == -1) { retval = errno; @@ -218,8 +233,34 @@ errcode_t ext2fs_image_super_write(ext2_filsys fs, int fd, /* * Now write out the block group descriptors */ + cp = (char *) fs->group_desc; + +#ifdef WORDS_BIGENDIAN + /* + * Convert group descriptors to little endian and back + * if needed + */ + groups_per_block = EXT2_DESC_PER_BLOCK(fs->super); + gdp = (struct ext2_group_desc *) cp; + for (j=0; j < groups_per_block*fs->desc_blocks; j++) { + gdp = ext2fs_group_desc(fs, fs->group_desc, j); + ext2fs_swap_group_desc2(fs, gdp); + } +#endif + actual = write(fd, cp, fs->blocksize * fs->desc_blocks); + + +#ifdef WORDS_BIGENDIAN + groups_per_block = EXT2_DESC_PER_BLOCK(fs->super); + gdp = (struct ext2_group_desc *) cp; + for (j=0; j < groups_per_block*fs->desc_blocks; j++) { + gdp = ext2fs_group_desc(fs, fs->group_desc, j); + ext2fs_swap_group_desc2(fs, gdp); + } +#endif + if (actual == -1) { retval = errno; goto errout; diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c index ad01a9fc5..015cfe4b5 100644 --- a/lib/ext2fs/inode.c +++ b/lib/ext2fs/inode.c @@ -770,7 +770,7 @@ errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, } if (fs->flags & EXT2_FLAG_IMAGE_FILE) { inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super); - block_nr = fs->image_header->offset_inode / fs->blocksize; + block_nr = ext2fs_le32_to_cpu(fs->image_header->offset_inode) / fs->blocksize; block_nr += (ino - 1) / inodes_per_block; offset = ((ino - 1) % inodes_per_block) * EXT2_INODE_SIZE(fs->super); diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c index 385d6e88c..532e70f7f 100644 --- a/lib/ext2fs/openfs.c +++ b/lib/ext2fs/openfs.c @@ -185,10 +185,10 @@ errcode_t ext2fs_open2(const char *name, const char *io_options, fs->image_header); if (retval) goto cleanup; - if (fs->image_header->magic_number != EXT2_ET_MAGIC_E2IMAGE) + if (ext2fs_le32_to_cpu(fs->image_header->magic_number) != EXT2_ET_MAGIC_E2IMAGE) return EXT2_ET_MAGIC_E2IMAGE; superblock = 1; - block_size = fs->image_header->fs_blocksize; + block_size = ext2fs_le32_to_cpu(fs->image_header->fs_blocksize); } /* diff --git a/lib/ext2fs/rw_bitmaps.c b/lib/ext2fs/rw_bitmaps.c index 0b532dbf9..e86bacd53 100644 --- a/lib/ext2fs/rw_bitmaps.c +++ b/lib/ext2fs/rw_bitmaps.c @@ -253,7 +253,7 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) ext2fs_free_mem(&buf); if (fs->flags & EXT2_FLAG_IMAGE_FILE) { - blk = (fs->image_header->offset_inodemap / fs->blocksize); + blk = (ext2fs_le32_to_cpu(fs->image_header->offset_inodemap) / fs->blocksize); ino_cnt = fs->super->s_inodes_count; while (inode_bitmap && ino_cnt > 0) { retval = io_channel_read_blk64(fs->image_io, blk++, @@ -270,7 +270,7 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) ino_itr += cnt; ino_cnt -= cnt; } - blk = (fs->image_header->offset_blockmap / + blk = (ext2fs_le32_to_cpu(fs->image_header->offset_blockmap) / fs->blocksize); blk_cnt = EXT2_GROUPS_TO_CLUSTERS(fs->super, fs->group_desc_count); diff --git a/misc/e2image.c b/misc/e2image.c index 5a18bb41d..83ae6335b 100644 --- a/misc/e2image.c +++ b/misc/e2image.c @@ -240,7 +240,7 @@ static void write_image_file(ext2_filsys fs, int fd) write_header(fd, NULL, sizeof(struct ext2_image_hdr), fs->blocksize); memset(&hdr, 0, sizeof(struct ext2_image_hdr)); - hdr.offset_super = seek_relative(fd, 0); + hdr.offset_super = ext2fs_cpu_to_le32(seek_relative(fd, 0)); retval = ext2fs_image_super_write(fs, fd, 0); if (retval) { com_err(program_name, retval, "%s", @@ -248,7 +248,7 @@ static void write_image_file(ext2_filsys fs, int fd) exit(1); } - hdr.offset_inode = seek_relative(fd, 0); + hdr.offset_inode = ext2fs_cpu_to_le32(seek_relative(fd, 0)); retval = ext2fs_image_inode_write(fs, fd, (fd != 1) ? IMAGER_FLAG_SPARSEWRITE : 0); if (retval) { @@ -257,7 +257,7 @@ static void write_image_file(ext2_filsys fs, int fd) exit(1); } - hdr.offset_blockmap = seek_relative(fd, 0); + hdr.offset_blockmap = ext2fs_cpu_to_le32(seek_relative(fd, 0)); retval = ext2fs_image_bitmap_write(fs, fd, 0); if (retval) { com_err(program_name, retval, "%s", @@ -265,7 +265,7 @@ static void write_image_file(ext2_filsys fs, int fd) exit(1); } - hdr.offset_inodemap = seek_relative(fd, 0); + hdr.offset_inodemap = ext2fs_cpu_to_le32(seek_relative(fd, 0)); retval = ext2fs_image_bitmap_write(fs, fd, IMAGER_FLAG_INODEMAP); if (retval) { com_err(program_name, retval, "%s", @@ -273,23 +273,23 @@ static void write_image_file(ext2_filsys fs, int fd) exit(1); } - hdr.magic_number = EXT2_ET_MAGIC_E2IMAGE; + hdr.magic_number = ext2fs_cpu_to_le32(EXT2_ET_MAGIC_E2IMAGE); strcpy(hdr.magic_descriptor, "Ext2 Image 1.0"); gethostname(hdr.fs_hostname, sizeof(hdr.fs_hostname)); strncpy(hdr.fs_device_name, device_name, sizeof(hdr.fs_device_name)-1); hdr.fs_device_name[sizeof(hdr.fs_device_name) - 1] = 0; - hdr.fs_blocksize = fs->blocksize; + hdr.fs_blocksize = ext2fs_cpu_to_le32(fs->blocksize); if (stat(device_name, &st) == 0) - hdr.fs_device = st.st_rdev; + hdr.fs_device = ext2fs_cpu_to_le32(st.st_rdev); if (fstat(fd, &st) == 0) { - hdr.image_device = st.st_dev; - hdr.image_inode = st.st_ino; + hdr.image_device = ext2fs_cpu_to_le32(st.st_dev); + hdr.image_inode = ext2fs_cpu_to_le32(st.st_ino); } memcpy(hdr.fs_uuid, fs->super->s_uuid, sizeof(hdr.fs_uuid)); - hdr.image_time = time(0); + hdr.image_time = ext2fs_cpu_to_le32(time(0)); write_header(fd, &hdr, sizeof(struct ext2_image_hdr), fs->blocksize); } @@ -1423,7 +1423,7 @@ static void install_image(char *device, char *image_fn, int type) ext2fs_rewrite_to_io(fs, io); - seek_set(fd, fs->image_header->offset_inode); + seek_set(fd, ext2fs_le32_to_cpu(fs->image_header->offset_inode)); retval = ext2fs_image_inode_read(fs, fd, 0); if (retval) {