From: "Gustavo A. R. Silva" gustavoars@kernel.org
[ 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@kernel.org Tested-by: Roberto Sassu roberto.sassu@huawei.com Reviewed-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Mimi Zohar zohar@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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