drew
/
acadia-newlib
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

nano-mallocr: Prevent NULL pointer de-reference in free_list 

The existing code checked if there was a chunk in free_list and
that the tail was not the next chunk.

The check if there is a chunk is not needed since it's already
known but the case of a single chunk in free_list needs to be
handled differently.
This commit is contained in:
Henrik Nilsson via Newlib 2023-02-17 06:56:49 +01:00 committed by Corinna Vinschen
parent 5011c8cc48
commit c8397ae817
1 changed files with 14 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
newlib/libc/stdlib/nano-mallocr.c
View File

@ -333,14 +333,23 @@ void * nano_malloc(RARG malloc_size_t s)
{ {
p->size += alloc_size; p->size += alloc_size;
/* Remove chunk from free_list */ /* Remove chunk from free_list. Since p != NULL there is
at least one chunk */
r = free_list; r = free_list;
while (r && p != r->next) if (r->next == NULL)
{
/* There is only a single chunk, remove it */
free_list = NULL;
}
else
{
/* Search for the chunk before the one to be removed */
while (p != r->next)
{ {
r = r->next; r = r->next;
} }
r->next = NULL; r->next = NULL;
}
r = p; r = p;
} }
else else