Fix instances of pointer addition with the NULL pointer

ubsan found undefined pointer addtions in
crypto/bio/bss_mem.c (mem_ctrl),
crypto/pem/pem_lib.c (PEM_read_bio_ex),
test/testutil/format_output.c (test_fail_string_common,
test_fail_memory_common).

Mostly a straight back-port-of: a07dc81

Additionally enable the ubsan run-checker, to prevent regressions.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/16423)

diff --git a/.github/workflows/run-checker-merge.yml b/.github/workflows/run-checker-merge.yml
index 29419a23968372f2851cb2509351ed3f57eae6e1..ff2d666b6da2b78709d22a2b51d63ff5b57de77e 100644 (file)
--- a/.github/workflows/run-checker-merge.yml
+++ b/.github/workflows/run-checker-merge.yml
@@ -16,8 +16,7 @@ jobs:
           no-engine no-shared,
           no-err,
           no-filenames,
-# ubsan build is temporarily disabled, due to failures to be investigated separately
-#          enable-ubsan no-asm -DPEDANTIC -DOPENSSL_SMALL_FOOTPRINT -fno-sanitize=alignment,
+          enable-ubsan no-asm -DPEDANTIC -DOPENSSL_SMALL_FOOTPRINT -fno-sanitize=alignment,
           no-unit-test,
           enable-weak-ssl-ciphers,
           enable-zlib,

diff --git a/crypto/bio/bss_mem.c b/crypto/bio/bss_mem.c
index 7cb4a57813fdcfc3b10b45eacd651795c47f1be4..14bfd00173f2a1743b72a68bb46bf9659e08e081 100644 (file)
--- a/crypto/bio/bss_mem.c
+++ b/crypto/bio/bss_mem.c
@@ -280,7 +280,7 @@ static long mem_ctrl(BIO *b, int cmd, long num, void *ptr)
         ret = (long)bm->length;
         if (ptr != NULL) {
             pptr = (char **)ptr;
-            *pptr = (char *)&(bm->data[0]);
+            *pptr = (char *)bm->data;
         }
         break;
     case BIO_C_SET_BUF_MEM:

diff --git a/crypto/pem/pem_lib.c b/crypto/pem/pem_lib.c
index a26322119aa7c968fbf61ab16e7486f72129d512..92dcd90a7f8ea174441c161bc3751da32ac03829 100644 (file)
--- a/crypto/pem/pem_lib.c
+++ b/crypto/pem/pem_lib.c
@@ -899,18 +899,13 @@ err:
 int PEM_read_bio_ex(BIO *bp, char **name_out, char **header,
                     unsigned char **data, long *len_out, unsigned int flags)
 {
-    EVP_ENCODE_CTX *ctx = EVP_ENCODE_CTX_new();
+    EVP_ENCODE_CTX *ctx = NULL;
     const BIO_METHOD *bmeth;
     BIO *headerB = NULL, *dataB = NULL;
     char *name = NULL;
     int len, taillen, headerlen, ret = 0;
     BUF_MEM * buf_mem;
 
-    if (ctx == NULL) {
-        PEMerr(PEM_F_PEM_READ_BIO_EX, ERR_R_MALLOC_FAILURE);
-        return 0;
-    }
-
     *len_out = 0;
     *name_out = *header = NULL;
     *data = NULL;
@@ -933,9 +928,20 @@ int PEM_read_bio_ex(BIO *bp, char **name_out, char **header,
     if (!get_header_and_data(bp, &headerB, &dataB, name, flags))
         goto end;
 
-    EVP_DecodeInit(ctx);
     BIO_get_mem_ptr(dataB, &buf_mem);
     len = buf_mem->length;
+
+    /* There was no data in the PEM file */
+    if (len == 0)
+        goto end;
+
+    ctx = EVP_ENCODE_CTX_new();
+    if (ctx == NULL) {
+        PEMerr(PEM_F_PEM_READ_BIO_EX, ERR_R_MALLOC_FAILURE);
+        goto end;
+    }
+
+    EVP_DecodeInit(ctx);
     if (EVP_DecodeUpdate(ctx, (unsigned char*)buf_mem->data, &len,
                          (unsigned char*)buf_mem->data, len) < 0
             || EVP_DecodeFinal(ctx, (unsigned char*)&(buf_mem->data[len]),
@@ -946,9 +952,6 @@ int PEM_read_bio_ex(BIO *bp, char **name_out, char **header,
     len += taillen;
     buf_mem->length = len;
 
-    /* There was no data in the PEM file; avoid malloc(0). */
-    if (len == 0)
-        goto end;
     headerlen = BIO_get_mem_data(headerB, NULL);
     *header = pem_malloc(headerlen + 1, flags);
     *data = pem_malloc(len, flags);

diff --git a/test/testutil/format_output.c b/test/testutil/format_output.c
index 6ee2a1d266c3c2b14b1b41bb722fbf9564bab399..f42141fd8d77d110058cf433142cf4d2e5a3012e 100644 (file)
--- a/test/testutil/format_output.c
+++ b/test/testutil/format_output.c
@@ -107,8 +107,10 @@ static void test_fail_string_common(const char *prefix, const char *file,
             if (diff && i > 0)
                 test_printf_stderr("% 4s    %s\n", "", bdiff);
         }
-        m1 += n1;
-        m2 += n2;
+        if (m1 != NULL)
+            m1 += n1;
+        if (m2 != NULL)
+            m2 += n2;
         l1 -= n1;
         l2 -= n2;
         cnt += width;
@@ -495,8 +497,10 @@ static void test_fail_memory_common(const char *prefix, const char *file,
             if (diff && i > 0)
                 test_printf_stderr("% 4s  %s\n", "", bdiff);
         }
-        m1 += n1;
-        m2 += n2;
+        if (m1 != NULL)
+            m1 += n1;
+        if (m2 != NULL)
+            m2 += n2;
         l1 -= n1;
         l2 -= n2;
         cnt += bytes;