Fix pointer arithmetic (invalid use of void in umm_poison_*)

rhempel · Sep 14, 2022 · 85f9a7f · 85f9a7f
1 parent 12b717c
commit 85f9a7f
Showing 1 changed file with 7 additions and 7 deletions.
diff --git a/src/umm_poison.c b/src/umm_poison.c
@@ -75,13 +75,13 @@ static bool check_poison_block(umm_block *pblock) {
         void *pc = (void *)pblock->body.data;
         void *pc_cur;
 
-        pc_cur = pc + sizeof(UMM_POISONED_BLOCK_LEN_TYPE);
+        pc_cur = (uint8_t *)pc + sizeof(UMM_POISONED_BLOCK_LEN_TYPE);
         if (!check_poison(pc_cur, UMM_POISON_SIZE_BEFORE, "before")) {
             ok = false;
             goto clean;
         }
 
-        pc_cur = pc + *((UMM_POISONED_BLOCK_LEN_TYPE *)pc) - UMM_POISON_SIZE_AFTER;
+        pc_cur = (uint8_t *)pc + *((UMM_POISONED_BLOCK_LEN_TYPE *)pc) - UMM_POISON_SIZE_AFTER;
         if (!check_poison(pc_cur, UMM_POISON_SIZE_AFTER, "after")) {
             ok = false;
             goto clean;
@@ -103,16 +103,16 @@ static void *get_poisoned(void *ptr, size_t size_w_poison) {
     if (size_w_poison != 0 && ptr != NULL) {
 
         /* Poison beginning and the end of the allocated chunk */
-        put_poison(ptr + sizeof(UMM_POISONED_BLOCK_LEN_TYPE),
+        put_poison((uint8_t *)ptr + sizeof(UMM_POISONED_BLOCK_LEN_TYPE),
             UMM_POISON_SIZE_BEFORE);
-        put_poison(ptr + size_w_poison - UMM_POISON_SIZE_AFTER,
+        put_poison((uint8_t *)ptr + size_w_poison - UMM_POISON_SIZE_AFTER,
             UMM_POISON_SIZE_AFTER);
 
         /* Put exact length of the user's chunk of memory */
         *(UMM_POISONED_BLOCK_LEN_TYPE *)ptr = (UMM_POISONED_BLOCK_LEN_TYPE)size_w_poison;
 
         /* Return pointer at the first non-poisoned byte */
-        return ptr + sizeof(UMM_POISONED_BLOCK_LEN_TYPE) + UMM_POISON_SIZE_BEFORE;
+        return (uint8_t *)ptr + sizeof(UMM_POISONED_BLOCK_LEN_TYPE) + UMM_POISON_SIZE_BEFORE;
     } else {
         return ptr;
     }
@@ -128,10 +128,10 @@ static void *get_unpoisoned(void *ptr) {
     if (ptr != NULL) {
         uint16_t c;
 
-        ptr -= (sizeof(UMM_POISONED_BLOCK_LEN_TYPE) + UMM_POISON_SIZE_BEFORE);
+        ptr = (uint8_t *)ptr - (sizeof(UMM_POISONED_BLOCK_LEN_TYPE) + UMM_POISON_SIZE_BEFORE);
 
         /* Figure out which block we're in. Note the use of truncated division... */
-        c = (((void *)ptr) - (void *)(&(UMM_HEAP[0]))) / UMM_BLOCKSIZE;
+        c = (((uint8_t *)ptr) - (uint8_t *)(&(UMM_HEAP[0]))) / UMM_BLOCKSIZE;
 
         check_poison_block(&UMM_BLOCK(c));
     }