UPSTREAM: firmware: arm_ffa: Explicitly cast return value from NOTIFICATION_INFO_GET

The return value ret.a2 is of type unsigned long and FFA_RET_NO_DATA is
a negative value.

Since the return value from the firmware can be just 32-bit even on
64-bit systems as FFA specification mentions it as int32 error code in
w0 register, explicitly casting to s32 ensures correct sign interpretation
when comparing against a signed error code FFA_RET_NO_DATA.

Without casting, comparison between unsigned long and a negative
constant could lead to unintended results due to type promotions.

Bug: 254441685
Fixes: 3522be48d82b ("firmware: arm_ffa: Implement the NOTIFICATION_INFO_GET interface")
Reported-by: Andrei Homescu <ahomescu@google.com>
Message-Id: <20250221095633.506678-2-sudeep.holla@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
(cherry picked from commit 3e282f41585c4dd49b688bd6395fd6f21a57c9f7)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: Ice50a86fc221736662ef711dcbc1232fd19ebcb4
This commit is contained in:
Sudeep Holla
2025-02-21 09:56:32 +00:00
committed by Lee Jones
parent 9126bec1d3
commit 421c7da597

View File

@@ -759,7 +759,7 @@ static void ffa_notification_info_get(void)
}, &ret);
if (ret.a0 != FFA_FN_NATIVE(SUCCESS) && ret.a0 != FFA_SUCCESS) {
if (ret.a2 != FFA_RET_NO_DATA)
if ((s32)ret.a2 != FFA_RET_NO_DATA)
pr_err("Notification Info fetch failed: 0x%lx (0x%lx)",
ret.a0, ret.a2);
return;