[PATCH v2 1/2] riscv/purgatory: return bool from verify_sha256_digest

[Thorsten Blum]

Change the function's return type from int to bool and return the result
of memcmp() directly to simplify the code.  While at it, cast ->start to
'const u8 *' to better match the expected type.

Signed-off-by: Thorsten Blum <thorsten.blum at linux.dev>
---
Changes in v2:
- Return true on success and false on failure (Eric)
- v1: https://lore.kernel.org/lkml/20260412194113.228703-4-thorsten.blum@linux.dev/
---
 arch/riscv/purgatory/purgatory.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/riscv/purgatory/purgatory.c b/arch/riscv/purgatory/purgatory.c
index bbd5cfa4d741..745deeb6e3a5 100644
--- a/arch/riscv/purgatory/purgatory.c
+++ b/arch/riscv/purgatory/purgatory.c
@@ -17,7 +17,7 @@ u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE] __section(".kexec-purgatory");
 
 struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX] __section(".kexec-purgatory");
 
-static int verify_sha256_digest(void)
+static bool verify_sha256_digest(void)
 {
 	struct kexec_sha_region *ptr, *end;
 	struct sha256_ctx sctx;
@@ -26,11 +26,10 @@ static int verify_sha256_digest(void)
 	sha256_init(&sctx);
 	end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions);
 	for (ptr = purgatory_sha_regions; ptr < end; ptr++)
-		sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len);
+		sha256_update(&sctx, (const u8 *)(ptr->start), ptr->len);
 	sha256_final(&sctx, digest);
-	if (memcmp(digest, purgatory_sha256_digest, sizeof(digest)) != 0)
-		return 1;
-	return 0;
+
+	return memcmp(digest, purgatory_sha256_digest, sizeof(digest)) == 0;
 }
 
 /* workaround for a warning with -Wmissing-prototypes */
@@ -38,7 +37,7 @@ void purgatory(void);
 
 void purgatory(void)
 {
-	if (verify_sha256_digest())
+	if (!verify_sha256_digest())
 		for (;;)
 			/* loop forever */
 			;