diff mbox series

[v9,1/2] lib: checksum: Fix type casting in checksum kunits

Message ID 20240221-fix_sparse_errors_checksum_tests-v9-1-bff4d73ab9d1@rivosinc.com
State New
Headers
Series lib: checksum: Fix issues with checksum tests |

Commit Message

Charlie Jenkins Feb. 22, 2024, 2:55 a.m. UTC 
  The checksum functions use the types __wsum and __sum16. These need to
be explicitly casted to, because will cause sparse errors otherwise.

Fixes: 6f4c45cbcb00 ("kunit: Add tests for csum_ipv6_magic and ip_fast_csum")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202401200106.PMTn6g56-lkp@intel.com/
Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
---
 lib/checksum_kunit.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

Comments

Christophe Leroy Feb. 23, 2024, 9:13 a.m. UTC | #1 
Le 22/02/2024 à 03:55, Charlie Jenkins a écrit :
> The checksum functions use the types __wsum and __sum16. These need to
> be explicitly casted to, because will cause sparse errors otherwise.

This is not the correct fix. When you forcibly cast, you shut up sparse 
and hide warnings but you don't fix the problem on big endian 
architectures which is what sparse reports to you.

In order to fix both the sparse warnings and the related issues, you 
have to perform proper endian conversion, similar to what was done with 
commit b38460bc463c ("kunit: Fix checksum tests on big endian CPUs")

The following change is what your patch should do:

diff --git a/lib/checksum_kunit.c b/lib/checksum_kunit.c
index 225bb7701460..bf70850035c7 100644
--- a/lib/checksum_kunit.c
+++ b/lib/checksum_kunit.c
@@ -215,7 +215,7 @@ static const u32 init_sums_no_overflow[] = {
  	0xffff0000, 0xfffffffb,
  };

-static const __sum16 expected_csum_ipv6_magic[] = {
+static const u16 expected_csum_ipv6_magic[] = {
  	0x18d4, 0x3085, 0x2e4b, 0xd9f4, 0xbdc8, 0x78f,	0x1034, 0x8422, 0x6fc0,
  	0xd2f6, 0xbeb5, 0x9d3,	0x7e2a, 0x312e, 0x778e, 0xc1bb, 0x7cf2, 0x9d1e,
  	0xca21, 0xf3ff, 0x7569, 0xb02e, 0xca86, 0x7e76, 0x4539, 0x45e3, 0xf28d,
@@ -241,7 +241,7 @@ static const __sum16 expected_csum_ipv6_magic[] = {
  	0x3845, 0x1014
  };

-static const __sum16 expected_fast_csum[] = {
+static const u16 expected_fast_csum[] = {
  	0xda83, 0x45da, 0x4f46, 0x4e4f, 0x34e,	0xe902, 0xa5e9, 0x87a5, 0x7187,
  	0x5671, 0xf556, 0x6df5, 0x816d, 0x8f81, 0xbb8f, 0xfbba, 0x5afb, 0xbe5a,
  	0xedbe, 0xabee, 0x6aac, 0xe6b,	0xea0d, 0x67ea, 0x7e68, 0x8a7e, 0x6f8a,
@@ -577,7 +577,8 @@ static void test_csum_no_carry_inputs(struct kunit 
*test)

  static void test_ip_fast_csum(struct kunit *test)
  {
-	__sum16 csum_result, expected;
+	__sum16 csum_result;
+	u16 expected;

  	for (int len = IPv4_MIN_WORDS; len < IPv4_MAX_WORDS; len++) {
  		for (int index = 0; index < NUM_IP_FAST_CSUM_TESTS; index++) {
@@ -586,7 +587,7 @@ static void test_ip_fast_csum(struct kunit *test)
  				expected_fast_csum[(len - IPv4_MIN_WORDS) *
  						   NUM_IP_FAST_CSUM_TESTS +
  						   index];
-			CHECK_EQ(expected, csum_result);
+			CHECK_EQ(to_sum16(expected), csum_result);
  		}
  	}
  }
@@ -598,7 +599,7 @@ static void test_csum_ipv6_magic(struct kunit *test)
  	const struct in6_addr *daddr;
  	unsigned int len;
  	unsigned char proto;
-	unsigned int csum;
+	__wsum csum;

  	const int daddr_offset = sizeof(struct in6_addr);
  	const int len_offset = sizeof(struct in6_addr) + sizeof(struct in6_addr);
@@ -611,10 +612,10 @@ static void test_csum_ipv6_magic(struct kunit *test)
  		saddr = (const struct in6_addr *)(random_buf + i);
  		daddr = (const struct in6_addr *)(random_buf + i +
  						  daddr_offset);
-		len = *(unsigned int *)(random_buf + i + len_offset);
+		len = le32_to_cpu(*(__le32 *)(random_buf + i + len_offset));
  		proto = *(random_buf + i + proto_offset);
-		csum = *(unsigned int *)(random_buf + i + csum_offset);
-		CHECK_EQ(expected_csum_ipv6_magic[i],
+		csum = *(__wsum *)(random_buf + i + csum_offset);
+		CHECK_EQ(to_sum16(expected_csum_ipv6_magic[i]),
  			 csum_ipv6_magic(saddr, daddr, len, proto, csum));
  	}
  #endif /* !CONFIG_NET */
---

Christophe
diff mbox series

Patch

diff --git a/lib/checksum_kunit.c b/lib/checksum_kunit.c
index 225bb7701460..776ad3d6d5a1 100644
--- a/lib/checksum_kunit.c
+++ b/lib/checksum_kunit.c
@@ -215,7 +215,7 @@  static const u32 init_sums_no_overflow[] = {
 	0xffff0000, 0xfffffffb,
 };
 
-static const __sum16 expected_csum_ipv6_magic[] = {
+static const u16 expected_csum_ipv6_magic[] = {
 	0x18d4, 0x3085, 0x2e4b, 0xd9f4, 0xbdc8, 0x78f,	0x1034, 0x8422, 0x6fc0,
 	0xd2f6, 0xbeb5, 0x9d3,	0x7e2a, 0x312e, 0x778e, 0xc1bb, 0x7cf2, 0x9d1e,
 	0xca21, 0xf3ff, 0x7569, 0xb02e, 0xca86, 0x7e76, 0x4539, 0x45e3, 0xf28d,
@@ -241,7 +241,7 @@  static const __sum16 expected_csum_ipv6_magic[] = {
 	0x3845, 0x1014
 };
 
-static const __sum16 expected_fast_csum[] = {
+static const u16 expected_fast_csum[] = {
 	0xda83, 0x45da, 0x4f46, 0x4e4f, 0x34e,	0xe902, 0xa5e9, 0x87a5, 0x7187,
 	0x5671, 0xf556, 0x6df5, 0x816d, 0x8f81, 0xbb8f, 0xfbba, 0x5afb, 0xbe5a,
 	0xedbe, 0xabee, 0x6aac, 0xe6b,	0xea0d, 0x67ea, 0x7e68, 0x8a7e, 0x6f8a,
@@ -582,7 +582,7 @@  static void test_ip_fast_csum(struct kunit *test)
 	for (int len = IPv4_MIN_WORDS; len < IPv4_MAX_WORDS; len++) {
 		for (int index = 0; index < NUM_IP_FAST_CSUM_TESTS; index++) {
 			csum_result = ip_fast_csum(random_buf + index, len);
-			expected =
+			expected = (__force __sum16)
 				expected_fast_csum[(len - IPv4_MIN_WORDS) *
 						   NUM_IP_FAST_CSUM_TESTS +
 						   index];
@@ -614,8 +614,9 @@  static void test_csum_ipv6_magic(struct kunit *test)
 		len = *(unsigned int *)(random_buf + i + len_offset);
 		proto = *(random_buf + i + proto_offset);
 		csum = *(unsigned int *)(random_buf + i + csum_offset);
-		CHECK_EQ(expected_csum_ipv6_magic[i],
-			 csum_ipv6_magic(saddr, daddr, len, proto, csum));
+		CHECK_EQ((__force __sum16)expected_csum_ipv6_magic[i],
+			 csum_ipv6_magic(saddr, daddr, len, proto,
+					 (__force __wsum)csum));
 	}
 #endif /* !CONFIG_NET */
 }