While loading each package ensure that the internal version matches the
expected database version to avoid the possibility to circumvent the
version check.
This issue can be used by an attacker to trick the software into
installing an older version. The behavior can be exploited by a
man-in-the-middle attack through specially crafted database tarball
containing a higher version, yet actually delivering an older and
vulnerable version, which was previously shipped.
Signed-off-by: Levente Polyak
Signed-off-by: Remi Gacogne
---
lib/libalpm/sync.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/lib/libalpm/sync.c b/lib/libalpm/sync.c
index 888ae15..8504e02 100644
--- a/lib/libalpm/sync.c
+++ b/lib/libalpm/sync.c
@@ -1212,6 +1212,7 @@ static int load_packages(alpm_handle_t *handle, alpm_list_t **data,
EVENT(handle, &event);
for(i = handle->trans->add; i; i = i->next, current++) {
+ int error = 0;
alpm_pkg_t *spkg = i->data;
char *filepath;
int percent = (int)(((double)current_bytes / total_bytes) * 100);
@@ -1232,6 +1233,21 @@ static int load_packages(alpm_handle_t *handle, alpm_list_t **data,
spkg->name);
alpm_pkg_t *pkgfile =_alpm_pkg_load_internal(handle, filepath, 1);
if(!pkgfile) {
+ _alpm_log(handle, ALPM_LOG_DEBUG, "failed to load pkgfile internal\n");
+ error = 1;
+ } else {
+ if(strcmp(spkg->name, pkgfile->name) != 0) {
+ _alpm_log(handle, ALPM_LOG_DEBUG, "internal package name missmatch, expected: '%s', actual: '%s'\n",
+ spkg->name, pkgfile->name);
+ error = 1;
+ }
+ if(alpm_pkg_vercmp(spkg->version, pkgfile->version) != 0) {
+ _alpm_log(handle, ALPM_LOG_DEBUG, "internal package version missmatch, expected: '%s', actual: '%s'\n",
+ spkg->version, pkgfile->version);
+ error = 1;
+ }
+ }
+ if(error != 0) {
errors++;
*data = alpm_list_add(*data, strdup(spkg->filename));
free(filepath);
--
2.4.6