| Message ID | ZrVBC9dGwukjfhet@cute (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [next] integrity: Use static_assert() to check struct sizes | expand |
On Thu, 2024-08-08 at 16:04 -0600, Gustavo A. R. Silva wrote: > 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. Looks good to me. Tested-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com> Thanks Roberto > Signed-off-by: Gustavo A. R. Silva <gustavoars@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 660f76cb69d3..c2c2da691123 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
On Thu, 2024-08-08 at 16:04 -0600, Gustavo A. R. Silva wrote: > 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> Sorry for the delay. It's now queued in next-integrity. thanks, Mimi
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 660f76cb69d3..c2c2da691123 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
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> --- security/integrity/integrity.h | 4 ++++ 1 file changed, 4 insertions(+)