From 64c71d7fc28c32ea61bf155bf1503646e4b1bf72 Mon Sep 17 00:00:00 2001 From: squimrel Date: Wed, 23 Aug 2017 04:21:14 +0000 Subject: [PATCH] Fix aligned alloc parameters and overflow on 32bit size_t (cherry picked from commit f802c54f736006566041aeb6a9d741a6d83ce687) --- libcheckisomd5.c | 3 ++- libimplantisomd5.c | 3 ++- utilities.c | 4 ++-- 3 files changed, 6 insertions(+), 4 deletions(-) diff --git a/libcheckisomd5.c b/libcheckisomd5.c index b190959..3ec3d88 100644 --- a/libcheckisomd5.c +++ b/libcheckisomd5.c @@ -49,6 +49,7 @@ static enum isomd5sum_status checkmd5sum(int isofd, checkCallback cb, void *cbda return ISOMD5SUM_CHECK_NOT_FOUND; const off_t total_size = info->isosize - info->skipsectors * SECTOR_SIZE; + const off_t fragment_size = total_size / (info->fragmentcount + 1); if (cb) cb(cbdata, 0, total_size); @@ -85,7 +86,7 @@ static enum isomd5sum_status checkmd5sum(int isofd, checkCallback cb, void *cbda MD5_Update(&hashctx, buffer, (unsigned int) nread); if (info->fragmentcount) { - const size_t current_fragment = (size_t)(offset * (off_t)(info->fragmentcount + 1) / total_size); + const size_t current_fragment = offset / fragment_size; const size_t fragmentsize = FRAGMENT_SUM_SIZE / info->fragmentcount; /* If we're onto the next fragment, calculate the previous sum and check. */ if (current_fragment != previous_fragment) { diff --git a/libimplantisomd5.c b/libimplantisomd5.c index 53801c8..47f21d7 100644 --- a/libimplantisomd5.c +++ b/libimplantisomd5.c @@ -106,6 +106,7 @@ int implantISOFD(int isofd, int supported, int forceit, int quiet, char **errstr buffer = aligned_alloc(pagesize, buffer_size * sizeof(*buffer)); const off_t total_size = isosize - SKIPSECTORS * SECTOR_SIZE; + const off_t fragment_size = total_size / (FRAGMENT_COUNT + 1); size_t previous_fragment = 0UL; off_t offset = 0LL; while (offset < total_size) { @@ -115,7 +116,7 @@ int implantISOFD(int isofd, int supported, int forceit, int quiet, char **errstr break; MD5_Update(&hashctx, buffer, (unsigned int) nread); - const size_t current_fragment = (size_t) offset * (FRAGMENT_COUNT + 1) / (size_t) total_size; + const size_t current_fragment = offset / fragment_size; const size_t fragmentsize = FRAGMENT_SUM_SIZE / FRAGMENT_COUNT; /* If we're onto the next fragment, calculate the previous sum and check. */ if (current_fragment != previous_fragment) { diff --git a/utilities.c b/utilities.c index b00337f..cfa84ed 100644 --- a/utilities.c +++ b/utilities.c @@ -131,9 +131,9 @@ struct volume_info *const parsepvd(const int isofd) { buffer[APPDATA_SIZE - 1] = '\0'; struct volume_info *result = malloc(sizeof(struct volume_info)); - result->skipsectors = 20; + result->skipsectors = SKIPSECTORS; result->supported = 0; - result->fragmentcount = 20; + result->fragmentcount = FRAGMENT_COUNT; result->offset = offset; result->isosize = isosize(aligned_buffer); -- 2.13.5