Fill the destination buffer with all set bits on error for fail-safety

of the caller's "< target" check in case the caller neglects to check for errors. CVS-ID: CHANGES 1.2 CVS-ID: yespower-opt.c 1.4 CVS-ID: yespower-ref.c 1.2
openwall · Jun 30, 2019 · d81b48a · d81b48a
1 parent 74dfcc0
commit d81b48a
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Showing 3 changed files with 16 additions and 7 deletions.
diff --git a/CHANGES b/CHANGES
@@ -1,5 +1,9 @@
 	Changes made between 1.0.0 (2018/07/12) and 1.0.1 (2019/06/30).
 
+Fill the destination buffer with all set bits on error for fail-safety
+of the caller's "< target" check in case the caller neglects to check
+for errors.
+
 Simplified SMix2 for its final invocation with Nloop=2 in yespower 0.5.
 
 Revised the "XOR of yespower" tests to trigger duplicate index in the

diff --git a/yespower-opt.c b/yespower-opt.c
@@ -1,6 +1,6 @@
 /*-
  * Copyright 2009 Colin Percival
- * Copyright 2012-2018 Alexander Peslyak
+ * Copyright 2012-2019 Alexander Peslyak
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -1049,7 +1049,7 @@ int yespower(yespower_local_t *local,
 	    (N & (N - 1)) != 0 ||
 	    (!pers && perslen)) {
 		errno = EINVAL;
-		return -1;
+		goto fail;
 	}
 
 	/* Allocate memory */
@@ -1067,9 +1067,9 @@ int yespower(yespower_local_t *local,
 	need = B_size + V_size + XY_size + ctx.Sbytes;
 	if (local->aligned_size < need) {
 		if (free_region(local))
-			return -1;
+			goto fail;
 		if (!alloc_region(local, need))
-			return -1;
+			goto fail;
 	}
 	B = (uint8_t *)local->aligned;
 	V = (salsa20_blk_t *)((uint8_t *)B + B_size);
@@ -1113,6 +1113,10 @@ int yespower(yespower_local_t *local,
 
 	/* Success! */
 	return 0;
+
+fail:
+	memset(dst, 0xff, sizeof(*dst));
+	return -1;
 }
 
 /**
@@ -1129,8 +1133,7 @@ int yespower_tls(const uint8_t *src, size_t srclen,
 	static __thread yespower_local_t local;
 
 	if (!initialized) {
-		if (yespower_init_local(&local))
-			return -1;
+		init_region(&local);
 		initialized = 1;
 	}
 

diff --git a/yespower-ref.c b/yespower-ref.c
@@ -1,6 +1,6 @@
 /*-
  * Copyright 2009 Colin Percival
- * Copyright 2013-2018 Alexander Peslyak
+ * Copyright 2013-2019 Alexander Peslyak
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -468,6 +468,8 @@ int yespower(yespower_local_t *local,
 	pwxform_ctx_t ctx;
 	uint32_t sha256[8];
 
+	memset(dst, 0xff, sizeof(*dst));
+
 	/* Sanity-check parameters */
 	if ((version != YESPOWER_0_5 && version != YESPOWER_1_0) ||
 	    N < 1024 || N > 512 * 1024 || r < 8 || r > 32 ||