diff options
Diffstat (limited to 'btrfs-show-super.c')
| -rw-r--r-- | btrfs-show-super.c | 79 |
1 files changed, 58 insertions, 21 deletions
diff --git a/btrfs-show-super.c b/btrfs-show-super.c index d8ad69e..051bd11 100644 --- a/btrfs-show-super.c +++ b/btrfs-show-super.c @@ -144,17 +144,15 @@ static int load_and_dump_sb(char *filename, int fd, u64 sb_bytenr, int full, ret = pread64(fd, super_block_data, BTRFS_SUPER_INFO_SIZE, sb_bytenr); if (ret != BTRFS_SUPER_INFO_SIZE) { - int e = errno; - /* check if the disk if too short for further superblock */ - if (ret == 0 && e == 0) + if (ret == 0 && errno == 0) return 0; fprintf(stderr, "ERROR: Failed to read the superblock on %s at %llu\n", filename, (unsigned long long)sb_bytenr); fprintf(stderr, - "ERROR: error = '%s', errno = %d\n", strerror(e), e); + "ERROR: error = '%s', errno = %d\n", strerror(errno), errno); return 1; } printf("superblock: bytenr=%llu, device=%s\n", sb_bytenr, filename); @@ -186,11 +184,14 @@ static void print_sys_chunk_array(struct btrfs_super_block *sb) struct extent_buffer *buf; struct btrfs_disk_key *disk_key; struct btrfs_chunk *chunk; - struct btrfs_key key; - u8 *ptr, *array_end; + u8 *array_ptr; + unsigned long sb_array_offset; u32 num_stripes; + u32 array_size; u32 len = 0; - int i = 0; + u32 cur_offset; + struct btrfs_key key; + int item; buf = malloc(sizeof(*buf) + sizeof(*sb)); if (!buf) { @@ -198,34 +199,70 @@ static void print_sys_chunk_array(struct btrfs_super_block *sb) exit(1); } write_extent_buffer(buf, sb, 0, sizeof(*sb)); - ptr = sb->sys_chunk_array; - array_end = ptr + btrfs_super_sys_array_size(sb); + array_size = btrfs_super_sys_array_size(sb); + + array_ptr = sb->sys_chunk_array; + sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array); + cur_offset = 0; + item = 0; + + while (cur_offset < array_size) { + disk_key = (struct btrfs_disk_key *)array_ptr; + len = sizeof(*disk_key); + if (cur_offset + len > array_size) + goto out_short_read; - while (ptr < array_end) { - disk_key = (struct btrfs_disk_key *)ptr; btrfs_disk_key_to_cpu(&key, disk_key); - printf("\titem %d ", i); - btrfs_print_key(disk_key); + array_ptr += len; + sb_array_offset += len; + cur_offset += len; - len = sizeof(*disk_key); + printf("\titem %d ", item); + btrfs_print_key(disk_key); putchar('\n'); - ptr += len; if (key.type == BTRFS_CHUNK_ITEM_KEY) { - chunk = (struct btrfs_chunk *)(ptr - (u8 *)sb); + chunk = (struct btrfs_chunk *)sb_array_offset; + /* + * At least one btrfs_chunk with one stripe must be + * present, exact stripe count check comes afterwards + */ + len = btrfs_chunk_item_size(1); + if (cur_offset + len > array_size) + goto out_short_read; + print_chunk(buf, chunk); num_stripes = btrfs_chunk_num_stripes(buf, chunk); + if (!num_stripes) { + printk( + "ERROR: invalid number of stripes %u in sys_array at offset %u\n", + num_stripes, cur_offset); + break; + } len = btrfs_chunk_item_size(num_stripes); + if (cur_offset + len > array_size) + goto out_short_read; } else { - BUG(); + printk( + "ERROR: unexpected item type %u in sys_array at offset %u\n", + (u32)key.type, cur_offset); + break; } + array_ptr += len; + sb_array_offset += len; + cur_offset += len; - ptr += len; - i++; + item++; } free(buf); + return; + +out_short_read: + printk("ERROR: sys_array too short to read %u bytes at offset %u\n", + len, cur_offset); + free(buf); } static int empty_backup(struct btrfs_root_backup *backup) @@ -295,7 +332,7 @@ struct readable_flag_entry { #define DEF_INCOMPAT_FLAG_ENTRY(bit_name) \ {BTRFS_FEATURE_INCOMPAT_##bit_name, #bit_name} -struct readable_flag_entry incompat_flags_array[] = { +static struct readable_flag_entry incompat_flags_array[] = { DEF_INCOMPAT_FLAG_ENTRY(MIXED_BACKREF), DEF_INCOMPAT_FLAG_ENTRY(DEFAULT_SUBVOL), DEF_INCOMPAT_FLAG_ENTRY(MIXED_GROUPS), @@ -315,7 +352,7 @@ static const int incompat_flags_num = sizeof(incompat_flags_array) / #define DEF_SUPER_FLAG_ENTRY(bit_name) \ {BTRFS_SUPER_FLAG_##bit_name, #bit_name} -struct readable_flag_entry super_flags_array[] = { +static struct readable_flag_entry super_flags_array[] = { DEF_HEADER_FLAG_ENTRY(WRITTEN), DEF_HEADER_FLAG_ENTRY(RELOC), DEF_SUPER_FLAG_ENTRY(CHANGING_FSID), |