diff options
Diffstat (limited to 'libdwfl/gzip.c')
| -rw-r--r-- | libdwfl/gzip.c | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/libdwfl/gzip.c b/libdwfl/gzip.c index 67f203f8..daf250bb 100644 --- a/libdwfl/gzip.c +++ b/libdwfl/gzip.c @@ -93,6 +93,34 @@ #define LINUX_MAGIC "HdrS" #define LINUX_MAX_SCAN 32768 +static void * +find_zImage_payload (void *buffer, size_t size) +{ + void *p = memmem (buffer, size, MAGIC, sizeof MAGIC - 1); +#ifdef LZMA + /* The raw LZMA format doesn't have any helpful header magic bytes to + match. So instead we just consider any byte that could possibly be + the start of an LZMA header, and try feeding the input to the decoder + to see if it likes the data. */ + if (p == NULL) + for (; size > 0; ++buffer, --size) + if (*(uint8_t *) buffer < (9 * 5 * 5)) + { + uint8_t dummy[512]; + lzma_stream z = { .next_in = buffer, .avail_in = size, + .next_out = dummy, .avail_out = sizeof dummy }; + int result = lzma_alone_decoder (&z, 1 << 30); + if (result != LZMA_OK) + break; + result = lzma_code (&z, LZMA_RUN); + lzma_end (&z); + if (result == LZMA_OK) + return buffer; + } +#endif + return p; +} + static bool mapped_zImage (off64_t *start_offset, void **mapped, size_t *mapped_size) { @@ -104,7 +132,7 @@ mapped_zImage (off64_t *start_offset, void **mapped, size_t *mapped_size) size_t scan = *mapped_size - pos; if (scan > LINUX_MAX_SCAN) scan = LINUX_MAX_SCAN; - void *p = memmem (*mapped + pos, scan, MAGIC, sizeof MAGIC - 1); + void *p = find_zImage_payload (*mapped + pos, scan); if (p != NULL) { *start_offset += p - *mapped; |