evas - psd loader - check read values to try make coverity happy

this is trying to fix CID 1402688, 1402687, 1402682, 1402665. not sure
it will or will not but it does dot i's and cross t's

1 files changed, 27 insertions, 11 deletions

diff --git a/src/modules/evas/image_loaders/psd/evas_image_load_psd.c b/src/modules/evas/image_loaders/psd/evas_image_load_psd.c
index 5dcf31039b..58cd961acf 100644
--- a/src/modules/evas/image_loaders/psd/evas_image_load_psd.c
+++ b/src/modules/evas/image_loaders/psd/evas_image_load_psd.c
@@ -61,7 +61,7 @@ static Eina_Bool get_compressed_channels_length(PSD_Header *Head,
 static int
 read_ushort(const unsigned char *map, size_t length, size_t *position, unsigned short *ret)
 {
-   if (*position + 2 > length) return 0;
+   if (((*position) + 2) > length) return 0;
    // FIXME: need to check order
    *ret = (map[(*position) + 0] << 8) | map[(*position) + 1];
    *position += 2;
@@ -71,7 +71,7 @@ read_ushort(const unsigned char *map, size_t length, size_t *position, unsigned
 static int
 read_uint(const unsigned char *map, size_t length, size_t *position, unsigned int *ret)
 {
-   if (*position + 4 > length) return 0;
+   if (((*position) + 4) > length) return 0;
    // FIXME: need to check order
    *ret = ARGB_JOIN(map[(*position) + 0], map[(*position) + 1], map[(*position) + 2], map[(*position) + 3]);
    *position += 4;
@@ -81,14 +81,14 @@ read_uint(const unsigned char *map, size_t length, size_t *position, unsigned in
 static int
 read_block(const unsigned char *map, size_t length, size_t *position, void *target, size_t size)
 {
-   if (*position + size > length) return 0;
+   if (((*position) + size) > length) return 0;
    memcpy(target, map + *position, size);
    *position += size;
    return 1;
 }
 
 // Internal function used to get the Psd header from the current file.
-Eina_Bool
+static Eina_Bool
 psd_get_header(PSD_Header *header, const unsigned char *map, size_t length, size_t *position)
 {
    unsigned short tmp;
@@ -114,7 +114,7 @@ psd_get_header(PSD_Header *header, const unsigned char *map, size_t length, size
 
 
 // Internal function used to check if the HEADER is a valid Psd header.
-Eina_Bool
+static Eina_Bool
 is_psd(PSD_Header *header)
 {
    if (strncmp((char*)header->signature, "8BPS", 4))
@@ -238,7 +238,7 @@ read_compressed_channel(const unsigned char *map, size_t length, size_t *positio
 }
 
 
-Eina_Bool
+static Eina_Bool
 psd_get_data(PSD_Header *head,
              const unsigned char *map, size_t length, size_t *position,
 	     unsigned char *buffer, Eina_Bool compressed,
@@ -492,7 +492,7 @@ psd_get_data(PSD_Header *head,
 }
 
 
-Eina_Bool
+static Eina_Bool
 get_single_channel(PSD_Header *head,
 		   const unsigned char *map, size_t length, size_t *position,
 		   unsigned char *buffer,
@@ -552,7 +552,7 @@ get_single_channel(PSD_Header *head,
    return EINA_TRUE;
 }
 
-Eina_Bool
+static Eina_Bool
 read_psd_grey(void *pixels, PSD_Header *head, const unsigned char *map, size_t length, size_t *position, int *error)
 {
    unsigned int color_mode, resource_size, misc_info;
@@ -566,15 +566,19 @@ read_psd_grey(void *pixels, PSD_Header *head, const unsigned char *map, size_t l
    CHECK_RET(read_uint(map, length, position, &color_mode));
    // Skip over the 'color mode data section'
    *position += color_mode;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_uint(map, length, position, &resource_size));
    // Read the 'image resources section'
    *position += resource_size;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_uint(map, length, position, &misc_info));
    *position += misc_info;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_ushort(map, length, position, &compressed));
+   if (compressed != 0) compressed = EINA_TRUE;
 
    head->channel_num = head->channels;
    // Temporary to read only one channel...some greyscale .psd files have 2.
@@ -602,7 +606,7 @@ read_psd_grey(void *pixels, PSD_Header *head, const unsigned char *map, size_t l
 }
 
 
-Eina_Bool
+static Eina_Bool
 read_psd_indexed(void *pixels, PSD_Header *head, const unsigned char *map, size_t length, size_t *position, int *error)
 {
    unsigned int color_mode, resource_size, misc_info;
@@ -624,15 +628,19 @@ read_psd_indexed(void *pixels, PSD_Header *head, const unsigned char *map, size_
    */
    // Skip over the 'color mode data section'
    *position += color_mode;
+   if ((*position) >= length) return EINA_FALSE;
 
    // Read the 'image resources section'
    CHECK_RET(read_uint(map, length, position, &resource_size));
    *position += resource_size;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_uint(map, length, position, &misc_info));
    *position += misc_info;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_ushort(map, length, position, &compressed));
+   if (compressed != 0) compressed = EINA_TRUE;
 
    if (head->channels != 1 || head->depth != 8)
      {
@@ -648,7 +656,7 @@ read_psd_indexed(void *pixels, PSD_Header *head, const unsigned char *map, size_
 #undef CHECK_RET
 }
 
-Eina_Bool
+static Eina_Bool
 read_psd_rgb(void *pixels, PSD_Header *head, const unsigned char *map, size_t length, size_t *position, int *error)
 {
    unsigned int color_mode, resource_size, misc_info;
@@ -660,15 +668,19 @@ read_psd_rgb(void *pixels, PSD_Header *head, const unsigned char *map, size_t le
    CHECK_RET(read_uint(map, length, position, &color_mode));
    // Skip over the 'color mode data section'
    *position += color_mode;
+   if ((*position) >= length) return EINA_FALSE;
 
    // Read the 'image resources section'
    CHECK_RET(read_uint(map, length, position, &resource_size));
    *position += resource_size;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_uint(map, length, position, &misc_info));
    *position += misc_info;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_ushort(map, length, position, &compressed));
+   if (compressed != 0) compressed = EINA_TRUE;
 
    head->channel_num = head->channels;
 
@@ -690,7 +702,7 @@ read_psd_rgb(void *pixels, PSD_Header *head, const unsigned char *map, size_t le
 #undef CHECK_RET
 }
 
-Eina_Bool
+static Eina_Bool
 read_psd_cmyk(Emile_Image_Property *prop, void *pixels, PSD_Header *head, const unsigned char *map, size_t length, size_t *position, int *error)
 {
    unsigned int color_mode, resource_size, misc_info, size, j, data_size;
@@ -707,15 +719,19 @@ read_psd_cmyk(Emile_Image_Property *prop, void *pixels, PSD_Header *head, const
    CHECK_RET(read_uint(map, length, position, &color_mode));
    // Skip over the 'color mode data section'
    *position += color_mode;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_uint(map, length, position, &resource_size));
    // Read the 'image resources section'
    *position += resource_size;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_uint(map, length, position, &misc_info));
    *position += misc_info;
+   if ((*position) >= length) return EINA_FALSE;
 
    CHECK_RET(read_ushort(map, length, position, &compressed));
+   if (compressed != 0) compressed = EINA_TRUE;
 
    switch (head->channels)
      {