From 4f0f586bf0c898233d8f316f471a21db2abd522d Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Thu, 8 Apr 2021 11:28:34 -0700 Subject: treewide: Change list_sort to use const pointers list_sort() internally casts the comparison function passed to it to a different type with constant struct list_head pointers, and uses this pointer to call the functions, which trips indirect call Control-Flow Integrity (CFI) checking. Instead of removing the consts, this change defines the list_cmp_func_t type and changes the comparison function types of all list_sort() callers to use const pointers, thus avoiding type mismatches. Suggested-by: Nick Desaulniers Signed-off-by: Sami Tolvanen Reviewed-by: Nick Desaulniers Reviewed-by: Christoph Hellwig Reviewed-by: Kees Cook Tested-by: Nick Desaulniers Tested-by: Nathan Chancellor Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20210408182843.1754385-10-samitolvanen@google.com --- include/linux/list_sort.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/include/linux/list_sort.h b/include/linux/list_sort.h index 20f178c24e9d..453105f74e05 100644 --- a/include/linux/list_sort.h +++ b/include/linux/list_sort.h @@ -6,8 +6,9 @@ struct list_head; +typedef int __attribute__((nonnull(2,3))) (*list_cmp_func_t)(void *, + const struct list_head *, const struct list_head *); + __attribute__((nonnull(2,3))) -void list_sort(void *priv, struct list_head *head, - int (*cmp)(void *priv, struct list_head *a, - struct list_head *b)); +void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp); #endif -- cgit v1.2.3