tpm: fix unsigned/signed mismatch errors related to __calc_tpm2_event_size

JIRA: https://issues.redhat.com/browse/RHEL-72764

Upstream Status: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

commit a066397
Author: Gregory Price <gourry@gourry.net>
Date:   Fri Sep 13 19:19:53 2024 -0400

    tpm: fix unsigned/signed mismatch errors related to __calc_tpm2_event_size

    __calc_tpm2_event_size returns 0 or a positive length, but return values
    are often interpreted as ints.  Convert everything over to u32 to avoid
    signed/unsigned logic errors.

    Signed-off-by: Gregory Price <gourry@gourry.net>
    Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Signed-off-by: Štěpán Horáček <shoracek@redhat.com>

Author: shoracek

drivers/firmware/efi/libstub/tpm.c

@@ -57,7 +57,7 @@ static void efi_retrieve_tcg2_eventlog(int version, efi_physical_addr_t log_loca
 	struct linux_efi_tpm_eventlog *log_tbl = NULL;
 	unsigned long first_entry_addr, last_entry_addr;
 	size_t log_size, last_entry_size;
-	int final_events_size = 0;
+	u32 final_events_size = 0;
 
 	first_entry_addr = (unsigned long) log_location;
 
@@ -110,9 +110,9 @@ static void efi_retrieve_tcg2_eventlog(int version, efi_physical_addr_t log_loca
 	 */
 	if (final_events_table && final_events_table->nr_events) {
 		struct tcg_pcr_event2_head *header;
-		int offset;
+		u32 offset;
 		void *data;
-		int event_size;
+		u32 event_size;
 		int i = final_events_table->nr_events;
 
 		data = (void *)final_events_table;

drivers/firmware/efi/tpm.c

@@ -19,7 +19,7 @@ EXPORT_SYMBOL(efi_tpm_final_log_size);
 static int __init tpm2_calc_event_log_size(void *data, int count, void *size_info)
 {
 	struct tcg_pcr_event2_head *header;
-	int event_size, size = 0;
+	u32 event_size, size = 0;
 
 	while (count > 0) {
 		header = data + size;

include/linux/tpm_eventlog.h

@@ -157,7 +157,7 @@ struct tcg_algorithm_info {
  * Return: size of the event on success, 0 on failure
  */
 
-static __always_inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
+static __always_inline u32 __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
 					 struct tcg_pcr_event *event_header,
 					 bool do_mapping)
 {