Skip to contentSkip to conversation

Input: Annotate struct input_leds with __counted_by

PATCH Applied Kees Cook 3 participants 3 messages Sep 22, 2023 – Sep 30, 2023

Subsystems (2)
HID Input drivers
lore
Share & tools
lore

Kees Cook

author
#0 lore raw

PATCH 1/1 Input: Annotate struct input_leds with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions).

As found with Coccinelle[1], add __counted_by for struct input_leds.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc Dmitry Torokhov <[email protected]>
Cc [email protected]
Signed-off-by Kees Cook <[email protected]>
---
 drivers/input/input-leds.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/input/input-leds.c +1 -1
index 0b11990ade46..0e935914bc3a 100644
@@ -44,7 +44,7 @@ struct input_led {
 struct input_leds {
 	struct input_handle handle;
 	unsigned int num_leds;
-	struct input_led leds[];
+	struct input_led leds[] __counted_by(num_leds);
 };
 
 static enum led_brightness input_leds_brightness_get(struct led_classdev *cdev)
Signature · 1 line
2.34.1
Reviewed-by on v1 1/1
#1 lore raw
Quoted 6 lines · Kees Cook

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions).

Quoted 7 lines

As found with Coccinelle[1], add __counted_by for struct input_leds.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc Dmitry Torokhov <[email protected]>
Cc [email protected]
Signed-off-by Kees Cook <[email protected]>
Reviewed-by Gustavo A. R. Silva <[email protected]>

Thanks

Signature · 1 line
Gustavo
Quoted 17 lines
---
  drivers/input/input-leds.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
drivers/input/input-leds.c +1 -1
index 0b11990ade46..0e935914bc3a 100644
@@ -44,7 +44,7 @@ struct input_led {
  struct input_leds {
  	struct input_handle handle;
  	unsigned int num_leds;
-	struct input_led leds[];
+	struct input_led leds[] __counted_by(num_leds);
  };
 
  static enum led_brightness input_leds_brightness_get(struct led_classdev *cdev)
maintainer Applied
#2 lore raw
In reply to Kees Cook
Quoted 6 lines · Kees Cook

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions).

Quoted 7 lines

As found with Coccinelle[1], add __counted_by for struct input_leds.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc Dmitry Torokhov <[email protected]>
Cc [email protected]
Signed-off-by Kees Cook <[email protected]>

Applied, thank you.

Signature · 1 line
Dmitry