From: Alejandro Lucero <alucerop@xxxxxxx> While resource_contains checks for IORESOURCE_UNSET flag for the resources given, if r1 was initialized with 0 size, the function returns a false positive. This is so because resource start and end fields are unsigned with end initialised to size - 1 by current resource macros. Make the function to check for the resource size for both resources since r2 with size 0 should not be considered as valid for the function purpose. Signed-off-by: Alejandro Lucero <alucerop@xxxxxxx> Suggested-by: Alison Schofield <alison.schofield@xxxxxxxxx> --- include/linux/ioport.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/linux/ioport.h b/include/linux/ioport.h index 6e9fb667a1c5..6cb8a8494508 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -264,6 +264,8 @@ static inline unsigned long resource_ext_type(const struct resource *res) /* True iff r1 completely contains r2 */ static inline bool resource_contains(const struct resource *r1, const struct resource *r2) { + if (!resource_size(r1) || !resource_size(r2)) + return false; if (resource_type(r1) != resource_type(r2)) return false; if (r1->flags & IORESOURCE_UNSET || r2->flags & IORESOURCE_UNSET) -- 2.17.1