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 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 ct_incoming_msg. Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> Cc: David Airlie <airlied@xxxxxxxxx> Cc: Daniel Vetter <daniel@xxxxxxxx> Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx> Cc: John Harrison <John.C.Harrison@xxxxxxxxx> Cc: Matthew Brost <matthew.brost@xxxxxxxxx> Cc: Michal Wajdeczko <michal.wajdeczko@xxxxxxxxx> Cc: Matt Roper <matthew.d.roper@xxxxxxxxx> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx Cc: linux-hardening@xxxxxxxxxxxxxxx Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c index 6e22af31513a..c33210ead1ef 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c @@ -96,7 +96,7 @@ struct ct_request { struct ct_incoming_msg { struct list_head link; u32 size; - u32 msg[]; + u32 msg[] __counted_by(size); }; enum { CTB_SEND = 0, CTB_RECV = 1 }; -- 2.34.1
