diff options
Diffstat (limited to '')
| -rw-r--r-- | src/liblzma/lz/lz_decoder.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/src/liblzma/lz/lz_decoder.c b/src/liblzma/lz/lz_decoder.c index bb21d0d0..6c9024e2 100644 --- a/src/liblzma/lz/lz_decoder.c +++ b/src/liblzma/lz/lz_decoder.c @@ -91,11 +91,17 @@ decode_buffer(lzma_coder *coder, in, in_pos, in_size); // Copy the decoded data from the dictionary to the out[] - // buffer. + // buffer. Do it conditionally because out can be NULL + // (in which case copy_size is always 0). Calling memcpy() + // with a null-pointer is undefined even if the third + // argument is 0. const size_t copy_size = coder->dict.pos - dict_start; assert(copy_size <= out_size - *out_pos); - memcpy(out + *out_pos, coder->dict.buf + dict_start, - copy_size); + + if (copy_size > 0) + memcpy(out + *out_pos, coder->dict.buf + dict_start, + copy_size); + *out_pos += copy_size; // Reset the dictionary if so requested by coder->lz.code(). |