tree 1b920bcdf9ad184491e3deec57dcbfc7396fafda
parent 682e01f79db6f175996be029319154b2600f40c3
author Nicolas Iooss <nicolas.iooss@m4x.org> 1491597866 +0200
committer Stephen Smalley <sds@tycho.nsa.gov> 1491934792 -0400

libselinux: do not dereference a NULL pointer when calloc() fails

selabel_is_digest_set() contains the following code:

        digest = calloc(1, sizeof(*digest));
        if (!digest)
            goto err;

    /* ... */

    err:
        free(digest->digest);

If calloc() failed, digest is NULL but is dereferenced when the
execution jumps to label err.

Check that digest is not NULL before freeing its fields.

This issue has been found using clang's static analyzer.

Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>