[PATCH][next] media: venus: hfi_cmds: Replace fake flex-arrays with flexible-array members

[PATCH][next] media: venus: hfi_cmds: Replace fake flex-arrays with flexible-array members

[Gustavo A. R. Silva]

One-element arrays are deprecated, and we are replacing them with flexible
array members instead. So, replace one-element arrays with flexible-array
members in multiple structures.

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -fstrict-flex-arrays=3 [1].

This results in no differences in binary output.

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/294
Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
 drivers/media/platform/qcom/venus/hfi_cmds.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/media/platform/qcom/venus/hfi_cmds.h b/drivers/media/platform/qcom/venus/hfi_cmds.h
index dd9c5066442d..55dd73ff073b 100644
--- a/drivers/media/platform/qcom/venus/hfi_cmds.h
+++ b/drivers/media/platform/qcom/venus/hfi_cmds.h
@@ -82,7 +82,7 @@ struct hfi_sys_set_buffers_pkt {
 	u32 buffer_type;
 	u32 buffer_size;
 	u32 num_buffers;
-	u32 buffer_addr[1];
+	u32 buffer_addr[];
 };
 
 struct hfi_sys_ping_pkt {
@@ -177,7 +177,7 @@ struct hfi_session_empty_buffer_uncompressed_plane1_pkt {
 	u32 filled_len;
 	u32 offset;
 	u32 packet_buffer2;
-	u32 data[1];
+	u32 data[];
 };
 
 struct hfi_session_empty_buffer_uncompressed_plane2_pkt {
@@ -186,7 +186,7 @@ struct hfi_session_empty_buffer_uncompressed_plane2_pkt {
 	u32 filled_len;
 	u32 offset;
 	u32 packet_buffer3;
-	u32 data[1];
+	u32 data[];
 };
 
 struct hfi_session_fill_buffer_pkt {
@@ -227,7 +227,7 @@ struct hfi_session_release_buffer_pkt {
 	u32 extradata_size;
 	u32 response_req;
 	u32 num_buffers;
-	u32 buffer_info[1];
+	u32 buffer_info[];
 };
 
 struct hfi_session_release_resources_pkt {
-- 
2.34.1

Re: [PATCH][next] media: venus: hfi_cmds: Replace fake flex-arrays with flexible-array members

[Kees Cook]

On Tue, May 16, 2023 at 07:18:01PM -0600, Gustavo A. R. Silva wrote:
> One-element arrays are deprecated, and we are replacing them with flexible
> array members instead. So, replace one-element arrays with flexible-array
> members in multiple structures.
> 
> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
> routines on memcpy() and help us make progress towards globally
> enabling -fstrict-flex-arrays=3 [1].
> 
> This results in no differences in binary output.
> 
> Link: https://github.com/KSPP/linux/issues/79
> Link: https://github.com/KSPP/linux/issues/294
> Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

The subject is very close to the related patch (plural vs non-plural):
https://lore.kernel.org/all/e4b13d7b79d1477e775c6d4564f7b23c4cf967f2.1684278538.git.gustavoars@kernel.org/

So it might be nice to name struct hfi_session_set_buffers_pkt
specifically in the other patch's subject, but otherwise:

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook