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crypto: qat - Use static_assert() to check struct sizes

PATCH In review Gustavo A. R. Silva 3 participants 3 messages Aug 8, 2024 – Aug 17, 2024

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Gustavo A. R. Silva

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PATCH 1/1 crypto: qat - Use static_assert() to check struct sizes

Commit 140e4c85d540 ("crypto: qat - Avoid -Wflex-array-member-not-at-end warnings") introduced tagged struct qat_alg_buf_list_hdr. We want to ensure that when new members need to be added to the flexible structure, they are always included within this tagged struct.

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 <[email protected]>
---
 drivers/crypto/intel/qat/qat_common/qat_bl.h | 2 ++
 1 file changed, 2 insertions(+)
drivers/crypto/intel/qat/qat_common/qat_bl.h +2 -0
index 85bc32a9ec0e..3f5b79015400 100644
@@ -23,6 +23,8 @@ struct qat_alg_buf_list {
 	);
 	struct qat_alg_buf buffers[];
 } __packed;
+static_assert(offsetof(struct qat_alg_buf_list, buffers) == sizeof(struct qat_alg_buf_list_hdr),
+	      "struct member likely outside of __struct_group()");
 
 struct qat_alg_fixed_buf_list {
 	struct qat_alg_buf_list_hdr sgl_hdr;
Signature · 1 line
2.34.1
maintainer Acked-by on v1 1/1
#1 lore raw
Quoted 10 lines · Gustavo A. R. Silva

Commit 140e4c85d540 ("crypto: qat - Avoid -Wflex-array-member-not-at-end warnings") introduced tagged struct qat_alg_buf_list_hdr. We want to ensure that when new members need to be added to the flexible structure, they are always included within this tagged struct.

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 <[email protected]>
Acked-by Giovanni Cabiddu <[email protected]>
maintainer
#2 lore raw
In reply to Gustavo A. R. Silva
Quoted 5 lines · Gustavo A. R. Silva

Commit 140e4c85d540 ("crypto: qat - Avoid -Wflex-array-member-not-at-end warnings") introduced tagged struct qat_alg_buf_list_hdr. We want to ensure that when new members need to be added to the flexible structure, they are always included within this tagged struct.

Quoted 8 lines

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 <[email protected]>
---
 drivers/crypto/intel/qat/qat_common/qat_bl.h | 2 ++
 1 file changed, 2 insertions(+)

Patch applied. Thanks.

Signature · 3 lines
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
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