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wmem: don't check whether sizeof(type) is <= 0. 

This should fix the cppcheck warning "The unsigned expression
'sizeof(struct _PKT_INFO)' will never be negative so it is either
pointless or an error to check if it is."

wmem_safe_mult() was only used to do an overflow-safe multiplication of
a type size and a count of elements of that type; replace it with
wmem_safe_mult_type_size(), which takes the type as the first argument,
and checks only whether the count of elements is <= 0.
This commit is contained in:
Guy Harris 2021-08-24 20:58:00 -07:00
parent d2979e1976
commit e490f93072
1 changed files with 9 additions and 4 deletions
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13
wsutil/wmem/wmem_core.h
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@ -81,8 +81,13 @@ G_GNUC_MALLOC;
#define wmem_new(allocator, type) \
((type*)wmem_alloc((allocator), sizeof(type)))
#define wmem_safe_mult(A, B) \
((((A) <= 0) || ((B) <= 0) || ((gsize)(A) > (G_MAXSSIZE / (gsize)(B)))) ? 0 : ((A) * (B)))
/*
* Overflow-safe multiplication of the size of a type by a number of
* items of that type, returning 0 if the result would overflow (or
* if the number of elements is negative), and the product otherwise.
*/
#define wmem_safe_mult_type_size(type, num) \
((((num) <= 0) || ((gsize)sizeof(type) > (G_MAXSSIZE / (gsize)(num)))) ? 0 : (sizeof(type) * (num)))
/** Allocate memory sufficient to hold n objects of the given type.
*
@ -92,7 +97,7 @@ G_GNUC_MALLOC;
* @return A void pointer to the newly allocated memory.
*/
#define wmem_alloc_array(allocator, type, num) \
((type*)wmem_alloc((allocator), wmem_safe_mult(sizeof(type), num)))
((type*)wmem_alloc((allocator), wmem_safe_mult_type_size(type, (num))))
/** Allocate the requested amount of memory in the given pool. Initializes the
* allocated memory with zeroes.
@ -125,7 +130,7 @@ G_GNUC_MALLOC;
* @return A void pointer to the newly allocated and zeroed memory.
*/
#define wmem_alloc0_array(allocator, type, num) \
((type*)wmem_alloc0((allocator), wmem_safe_mult(sizeof(type), (num))))
((type*)wmem_alloc0((allocator), wmem_safe_mult_type_size(type, (num))))
/** Returns the allocated memory to the allocator. This function should only
* be called directly by allocators when the allocated block is sufficiently