libFLAC: Add function safe_realloc_()
authorErik de Castro Lopo <erikd@mega-nerd.com>
Sat, 22 Aug 2015 09:22:50 +0000 (19:22 +1000)
committerErik de Castro Lopo <erikd@mega-nerd.com>
Sat, 22 Aug 2015 09:39:37 +0000 (19:39 +1000)
The new function wraps, realloc() and if the realloc() fails, it
free()s the old pointer.

This is an improvement on the potential realloc() memory leak that
was fixed in 15a9062609.

Still needs fuzzing to validate it.

include/share/alloc.h
src/libFLAC/format.c
src/libFLAC/md5.c
src/libFLAC/metadata_object.c
src/share/replaygain_analysis/replaygain_analysis.c

index 5e1f1e2..3b70749 100644 (file)
@@ -153,11 +153,21 @@ static inline void *safe_malloc_muladd2_(size_t size1, size_t size2, size_t size
        return malloc(size1*size2);
 }
 
+static inline void *safe_realloc_(void *ptr, size_t size)
+{
+       void *oldptr = ptr;
+       void *newptr = realloc(ptr, size);
+       if(size > 0 && newptr == 0)
+               free(oldptr);
+       return newptr;
+}
 static inline void *safe_realloc_add_2op_(void *ptr, size_t size1, size_t size2)
 {
        size2 += size1;
-       if(size2 < size1)
+       if(size2 < size1) {
+               free(ptr);
                return 0;
+       }
        return realloc(ptr, size2);
 }
 
@@ -192,7 +202,7 @@ static inline void *safe_realloc_mul_2op_(void *ptr, size_t size1, size_t size2)
                return realloc(ptr, 0); /* preserve POSIX realloc(ptr, 0) semantics */
        if(size1 > SIZE_MAX / size2)
                return 0;
-       return realloc(ptr, size1*size2);
+       return safe_realloc_(ptr, size1*size2);
 }
 
 /* size1 * (size2 + size3) */
index 5215c56..0f601af 100644 (file)
@@ -39,6 +39,7 @@
 #include <string.h> /* for memset() */
 #include "FLAC/assert.h"
 #include "FLAC/format.h"
+#include "share/alloc.h"
 #include "share/compat.h"
 #include "private/format.h"
 #include "private/macros.h"
@@ -573,17 +574,10 @@ FLAC__bool FLAC__format_entropy_coding_method_partitioned_rice_contents_ensure_s
        FLAC__ASSERT(object->capacity_by_order > 0 || (0 == object->parameters && 0 == object->raw_bits));
 
        if(object->capacity_by_order < max_partition_order) {
-               void *oldptr;
-               oldptr = object->parameters;
-               if(0 == (object->parameters = realloc(object->parameters, sizeof(unsigned)*(1 << max_partition_order)))) {
-                       free(oldptr);
+               if(0 == (object->parameters = safe_realloc_(object->parameters, sizeof(unsigned)*(1 << max_partition_order))))
                        return false;
-               }
-               oldptr = object->raw_bits;
-               if(0 == (object->raw_bits = realloc(object->raw_bits, sizeof(unsigned)*(1 << max_partition_order)))) {
-                       free(oldptr);
+               if(0 == (object->raw_bits = safe_realloc_(object->raw_bits, sizeof(unsigned)*(1 << max_partition_order))))
                        return false;
-               }
                memset(object->raw_bits, 0, sizeof(unsigned)*(1 << max_partition_order));
                object->capacity_by_order = max_partition_order;
        }
index 051efe1..05f824d 100644 (file)
@@ -499,9 +499,8 @@ FLAC__bool FLAC__MD5Accumulate(FLAC__MD5Context *ctx, const FLAC__int32 * const
                return false;
 
        if (ctx->capacity < bytes_needed) {
-               FLAC__byte *tmp = realloc(ctx->internal_buf.p8, bytes_needed);
+               FLAC__byte *tmp = safe_realloc_(ctx->internal_buf.p8, bytes_needed);
                if (0 == tmp) {
-                       free(ctx->internal_buf.p8);
                        if (0 == (ctx->internal_buf.p8 = safe_malloc_(bytes_needed)))
                                return false;
                }
index 1bfa0b4..ebe9801 100644 (file)
@@ -954,13 +954,8 @@ FLAC_API FLAC__bool FLAC__metadata_object_seektable_resize_points(FLAC__StreamMe
                        free(object->data.seek_table.points);
                        object->data.seek_table.points = 0;
                }
-               else {
-                       void *oldptr = object->data.seek_table.points;
-                       if(0 == (object->data.seek_table.points = realloc(object->data.seek_table.points, new_size))) {
-                               free(oldptr);
-                               return false;
-                       }
-               }
+               else if(0 == (object->data.seek_table.points = safe_realloc_(object->data.seek_table.points, new_size)))
+                       return false;
 
                /* if growing, set new elements to placeholders */
                if(new_size > old_size) {
@@ -1205,13 +1200,9 @@ FLAC_API FLAC__bool FLAC__metadata_object_vorbiscomment_resize_comments(FLAC__St
                        free(object->data.vorbis_comment.comments);
                        object->data.vorbis_comment.comments = 0;
                }
-               else {
-                       FLAC__StreamMetadata_VorbisComment_Entry *oldptr = object->data.vorbis_comment.comments;
-                       if(0 == (object->data.vorbis_comment.comments = realloc(object->data.vorbis_comment.comments, new_size))) {
-                               vorbiscomment_entry_array_delete_(oldptr, object->data.vorbis_comment.num_comments);
-                               object->data.vorbis_comment.num_comments = 0;
-                               return false;
-                       }
+               else if(0 == (object->data.vorbis_comment.comments = safe_realloc_(object->data.vorbis_comment.comments, new_size))) {
+                       object->data.vorbis_comment.num_comments = 0;
+                       return false;
                }
 
                /* if growing, zero all the length/pointers of new elements */
@@ -1513,13 +1504,8 @@ FLAC_API FLAC__bool FLAC__metadata_object_cuesheet_track_resize_indices(FLAC__St
                        free(track->indices);
                        track->indices = 0;
                }
-               else {
-                       void *oldptr = track->indices;
-                       if(0 == (track->indices = realloc(track->indices, new_size))) {
-                               free(oldptr);
-                               return false;
-                       }
-               }
+               else if(0 == (track->indices = safe_realloc_(track->indices, new_size)))
+                       return false;
 
                /* if growing, zero all the lengths/pointers of new elements */
                if(new_size > old_size)
@@ -1613,13 +1599,8 @@ FLAC_API FLAC__bool FLAC__metadata_object_cuesheet_resize_tracks(FLAC__StreamMet
                        free(object->data.cue_sheet.tracks);
                        object->data.cue_sheet.tracks = 0;
                }
-               else {
-                       void *oldptr = object->data.cue_sheet.tracks;
-                       if(0 == (object->data.cue_sheet.tracks = realloc(object->data.cue_sheet.tracks, new_size))) {
-                               free(oldptr);
-                               return false;
-                       }
-               }
+               else if(0 == (object->data.cue_sheet.tracks = safe_realloc_(object->data.cue_sheet.tracks, new_size)))
+                       return false;
 
                /* if growing, zero all the lengths/pointers of new elements */
                if(new_size > old_size)
index 7611cf9..20a5b28 100644 (file)
@@ -97,6 +97,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>
+#include "share/alloc.h"
 #include "share/compat.h"
 #include "share/replaygain_analysis.h"
 
@@ -339,13 +340,8 @@ CreateGainFilter ( long samplefreq )
 static void*
 ReallocateWindowBuffer(unsigned window_size, flac_float_t **window_buffer)
 {
-    void *p = realloc(
-        *window_buffer, sizeof(**window_buffer) * (window_size + MAX_ORDER));
-
-    if (p)
-        *window_buffer = p;
-
-    return p;
+    *window_buffer = safe_realloc_(*window_buffer, sizeof(**window_buffer) * (window_size + MAX_ORDER));
+    return *window_buffer;
 }
 
 static int