diff mbox series

[v8,10/27] resource: harden resource_contains

Message ID 20241216161042.42108-11-alejandro.lucero-palau@amd.com
State New
Headers show
Series cxl: add type2 device basic support | expand

Commit Message

Lucero Palau, Alejandro Dec. 16, 2024, 4:10 p.m. UTC 
From: Alejandro Lucero <alucerop@amd.com>

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@amd.com>
Suggested-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
---
 include/linux/ioport.h | 2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 5385349f0b8a..7ba31a222536 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -296,6 +296,8 @@  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)