diff options
| -rw-r--r-- | archival/libarchive/decompress_unxz.c | 43 |
1 files changed, 36 insertions, 7 deletions
diff --git a/archival/libarchive/decompress_unxz.c b/archival/libarchive/decompress_unxz.c index 79b48a152..e9ddd3709 100644 --- a/archival/libarchive/decompress_unxz.c +++ b/archival/libarchive/decompress_unxz.c @@ -40,6 +40,7 @@ static uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc) IF_DESKTOP(long long) int FAST_FUNC unpack_xz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd) { + enum xz_ret xz_result; struct xz_buf iobuf; struct xz_dec *state; unsigned char *membuf; @@ -63,9 +64,8 @@ unpack_xz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd) /* Limit memory usage to about 64 MiB. */ state = xz_dec_init(XZ_DYNALLOC, 64*1024*1024); + xz_result = X_OK; while (1) { - enum xz_ret r; - if (iobuf.in_pos == iobuf.in_size) { int rd = safe_read(src_fd, membuf, BUFSIZ); if (rd < 0) { @@ -73,28 +73,57 @@ unpack_xz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd) total = -1; break; } + if (rd == 0 && xz_result == XZ_STREAM_END) + break; iobuf.in_size = rd; iobuf.in_pos = 0; } + if (xz_result == XZ_STREAM_END) { + /* + * Try to start decoding next concatenated stream. + * Stream padding must always be a multiple of four + * bytes to preserve four-byte alignment. To keep the + * code slightly smaller, we aren't as strict here as + * the .xz spec requires. We just skip all zero-bytes + * without checking the alignment and thus can accept + * files that aren't valid, e.g. the XZ utils test + * files bad-0pad-empty.xz and bad-0catpad-empty.xz. + */ + do { + if (membuf[iobuf.in_pos] != 0) { + xz_dec_reset(state); + goto do_run; + } + iobuf.in_pos++; + } while (iobuf.in_pos < iobuf.in_size); + } + do_run: // bb_error_msg(">in pos:%d size:%d out pos:%d size:%d", // iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size); - r = xz_dec_run(state, &iobuf); + xz_result = xz_dec_run(state, &iobuf); // bb_error_msg("<in pos:%d size:%d out pos:%d size:%d r:%d", -// iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size, r); +// iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size, xz_result); if (iobuf.out_pos) { xwrite(dst_fd, iobuf.out, iobuf.out_pos); IF_DESKTOP(total += iobuf.out_pos;) iobuf.out_pos = 0; } - if (r == XZ_STREAM_END) { - break; + if (xz_result == XZ_STREAM_END) { + /* + * Can just "break;" here, if not for concatenated + * .xz streams. + * Checking for padding may require buffer + * replenishment. Can't do it here. + */ + continue; } - if (r != XZ_OK && r != XZ_UNSUPPORTED_CHECK) { + if (xz_result != XZ_OK && xz_result != XZ_UNSUPPORTED_CHECK) { bb_error_msg("corrupted data"); total = -1; break; } } + xz_dec_end(state); free(membuf); |