From: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
[ Upstream commit 08ae3e5f5fc8edb9bd0c7ef9696ff29ef18b26ef ]
Commit 38aa3f5ac6d2 ("integrity: Avoid -Wflex-array-member-not-at-end
warnings") introduced tagged `struct evm_ima_xattr_data_hdr` and
`struct ima_digest_data_hdr`. We want to ensure that when new members
need to be added to the flexible structures, they are always included
within these tagged structs.
So, we use `static_assert()` to ensure that the memory layout for
both the flexible structure and the tagged struct is the same after
any changes.
Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
Tested-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
Reviewed-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
security/integrity/integrity.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index 660f76cb69d37..c2c2da6911233 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -37,6 +37,8 @@ struct evm_ima_xattr_data {
);
u8 data[];
} __packed;
+static_assert(offsetof(struct evm_ima_xattr_data, data) == sizeof(struct evm_ima_xattr_data_hdr),
+ "struct member likely outside of __struct_group()");
/* Only used in the EVM HMAC code. */
struct evm_xattr {
@@ -65,6 +67,8 @@ struct ima_digest_data {
);
u8 digest[];
} __packed;
+static_assert(offsetof(struct ima_digest_data, digest) == sizeof(struct ima_digest_data_hdr),
+ "struct member likely outside of __struct_group()");
/*
* Instead of wrapping the ima_digest_data struct inside a local structure
--
2.43.0
