getaddrinfo: Get rid of alloca

Use a scratch_buffer rather than alloca to avoid potential stack
overflow.
This commit is contained in:
Joe Simmons-Talbott 2023-09-06 13:32:46 +00:00
parent 3d6fcf1bd7
commit 955a47a4bf

View File

@ -2404,22 +2404,17 @@ getaddrinfo (const char *name, const char *service,
struct addrinfo *q;
struct addrinfo *last = NULL;
char *canonname = NULL;
bool malloc_results;
size_t alloc_size = nresults * (sizeof (*results) + sizeof (size_t));
struct scratch_buffer buf;
scratch_buffer_init (&buf);
malloc_results
= !__libc_use_alloca (alloc_size);
if (malloc_results)
if (!scratch_buffer_set_array_size (&buf, nresults,
sizeof (*results) + sizeof (size_t)))
{
results = malloc (alloc_size);
if (results == NULL)
{
__free_in6ai (in6ai);
return EAI_MEMORY;
}
__free_in6ai (in6ai);
return EAI_MEMORY;
}
else
results = alloca (alloc_size);
results = buf.data;
order = (size_t *) (results + nresults);
/* Now we definitely need the interface information. */
@ -2590,8 +2585,7 @@ getaddrinfo (const char *name, const char *service,
/* Fill in the canonical name into the new first entry. */
p->ai_canonname = canonname;
if (malloc_results)
free (results);
scratch_buffer_free (&buf);
}
__free_in6ai (in6ai);