[PATCH AUTOSEL 6.1 33/34] apparmor: fix use of strcpy in policy_unpack_test

From: Sasha Levin
Date: Sun Jul 23 2023 - 21:44:26 EST


From: Rae Moar <rmoar@xxxxxxxxxx>

[ Upstream commit b54aebd4411134b525a82d663a26b2f135ecb7e8 ]

Replace the use of strcpy() in build_aa_ext_struct() in
policy_unpack_test.c with strscpy().

strscpy() is the safer method to use to ensure the buffer does not
overflow. This was found by kernel test robot:
https://lore.kernel.org/all/202301040348.NbfVsXO0-lkp@xxxxxxxxx/.

Reported-by: kernel test robot <lkp@xxxxxxxxx>

Signed-off-by: Rae Moar <rmoar@xxxxxxxxxx>
Signed-off-by: John Johansen <john.johansen@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
security/apparmor/policy_unpack_test.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/security/apparmor/policy_unpack_test.c b/security/apparmor/policy_unpack_test.c
index 0a969b2e03dba..64ddea559f9ac 100644
--- a/security/apparmor/policy_unpack_test.c
+++ b/security/apparmor/policy_unpack_test.c
@@ -66,31 +66,30 @@ static struct aa_ext *build_aa_ext_struct(struct policy_unpack_fixture *puf,

*buf = AA_NAME;
*(buf + 1) = strlen(TEST_STRING_NAME) + 1;
- strcpy(buf + 3, TEST_STRING_NAME);
+ strscpy(buf + 3, TEST_STRING_NAME, e->end - (void *)(buf + 3));

buf = e->start + TEST_STRING_BUF_OFFSET;
*buf = AA_STRING;
*(buf + 1) = strlen(TEST_STRING_DATA) + 1;
- strcpy(buf + 3, TEST_STRING_DATA);
-
+ strscpy(buf + 3, TEST_STRING_DATA, e->end - (void *)(buf + 3));
buf = e->start + TEST_NAMED_U32_BUF_OFFSET;
*buf = AA_NAME;
*(buf + 1) = strlen(TEST_U32_NAME) + 1;
- strcpy(buf + 3, TEST_U32_NAME);
+ strscpy(buf + 3, TEST_U32_NAME, e->end - (void *)(buf + 3));
*(buf + 3 + strlen(TEST_U32_NAME) + 1) = AA_U32;
*((u32 *)(buf + 3 + strlen(TEST_U32_NAME) + 2)) = TEST_U32_DATA;

buf = e->start + TEST_NAMED_U64_BUF_OFFSET;
*buf = AA_NAME;
*(buf + 1) = strlen(TEST_U64_NAME) + 1;
- strcpy(buf + 3, TEST_U64_NAME);
+ strscpy(buf + 3, TEST_U64_NAME, e->end - (void *)(buf + 3));
*(buf + 3 + strlen(TEST_U64_NAME) + 1) = AA_U64;
*((u64 *)(buf + 3 + strlen(TEST_U64_NAME) + 2)) = TEST_U64_DATA;

buf = e->start + TEST_NAMED_BLOB_BUF_OFFSET;
*buf = AA_NAME;
*(buf + 1) = strlen(TEST_BLOB_NAME) + 1;
- strcpy(buf + 3, TEST_BLOB_NAME);
+ strscpy(buf + 3, TEST_BLOB_NAME, e->end - (void *)(buf + 3));
*(buf + 3 + strlen(TEST_BLOB_NAME) + 1) = AA_BLOB;
*(buf + 3 + strlen(TEST_BLOB_NAME) + 2) = TEST_BLOB_DATA_SIZE;
memcpy(buf + 3 + strlen(TEST_BLOB_NAME) + 6,
@@ -99,7 +98,7 @@ static struct aa_ext *build_aa_ext_struct(struct policy_unpack_fixture *puf,
buf = e->start + TEST_NAMED_ARRAY_BUF_OFFSET;
*buf = AA_NAME;
*(buf + 1) = strlen(TEST_ARRAY_NAME) + 1;
- strcpy(buf + 3, TEST_ARRAY_NAME);
+ strscpy(buf + 3, TEST_ARRAY_NAME, e->end - (void *)(buf + 3));
*(buf + 3 + strlen(TEST_ARRAY_NAME) + 1) = AA_ARRAY;
*((u16 *)(buf + 3 + strlen(TEST_ARRAY_NAME) + 2)) = TEST_ARRAY_SIZE;

--
2.39.2