Hi all,
Friendly ping: who can take this, please?
Thanks
--
Gustavo
On 6/3/21 19:43, Gustavo A. R. Silva wrote:
> There is a regular need in the kernel to provide a way to declare having
> a dynamically sized set of trailing elements in a structure. Kernel code
> should always use “flexible array members”[1] for these cases. The older
> style of one-element or zero-length arrays should no longer be used[2].
>
> Use flexible-array members in struct hfi_msg_sys_property_info_pkt and
> hfi_msg_session_property_info_pkt instead of one-element arrays, and
> refactor the code accordingly.
>
> Also, this helps with the ongoing efforts to enable -Warray-bounds by
> fixing the following warnings:
>
> CC [M] drivers/media/platform/qcom/venus/hfi_msgs.o
> drivers/media/platform/qcom/venus/hfi_msgs.c: In function ‘hfi_sys_property_info’:
> drivers/media/platform/qcom/venus/hfi_msgs.c:246:35: warning: array subscript 1 is above array bounds of ‘u32[1]’ {aka ‘unsigned int[1]’} [-Warray-bounds]
> 246 | if (req_bytes < 128 || !pkt->data[1] || pkt->num_properties > 1)
> | ~~~~~~~~~^~~
> drivers/media/platform/qcom/venus/hfi_msgs.c: In function ‘hfi_session_prop_info’:
> drivers/media/platform/qcom/venus/hfi_msgs.c:342:62: warning: array subscript 1 is above array bounds of ‘u32[1]’ {aka ‘unsigned int[1]’} [-Warray-bounds]
> 342 | if (!req_bytes || req_bytes % sizeof(*buf_req) || !pkt->data[1])
> | ~~~~~~~~~^~~
>
> [1] https://en.wikipedia.org/wiki/Flexible_array_member
> [2] https://www.kernel.org/doc/html/v5.9/process/deprecated.html#zero-length-and-one-element-arrays
>
> Link: https://github.com/KSPP/linux/issues/79
> Link: https://github.com/KSPP/linux/issues/109
> Co-developed-by: Kees Cook <keescook@xxxxxxxxxxxx>
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
> ---
> Changes in v2:
> - Fix packet size calculation by adding member _property_ to
> both structutures hfi_msg_sys_property_info_pkt and
> hfi_msg_session_property_info_pkt, and refactor the code
> accordingly.
>
> JFYI: We are about to be able to globally enable -Warray-bounds and,
> these are pretty much the last out-of-bounds warnings in linux-next. :)
>
> drivers/media/platform/qcom/venus/hfi_msgs.c | 16 ++++++++--------
> drivers/media/platform/qcom/venus/hfi_msgs.h | 6 ++++--
> 2 files changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/media/platform/qcom/venus/hfi_msgs.c b/drivers/media/platform/qcom/venus/hfi_msgs.c
> index a2d436d407b2..d9fde66f6fa8 100644
> --- a/drivers/media/platform/qcom/venus/hfi_msgs.c
> +++ b/drivers/media/platform/qcom/venus/hfi_msgs.c
> @@ -251,11 +251,11 @@ sys_get_prop_image_version(struct device *dev,
>
> req_bytes = pkt->hdr.size - sizeof(*pkt);
>
> - if (req_bytes < VER_STR_SZ || !pkt->data[1] || pkt->num_properties > 1)
> + if (req_bytes < VER_STR_SZ || !pkt->data[0] || pkt->num_properties > 1)
> /* bad packet */
> return;
>
> - img_ver = (u8 *)&pkt->data[1];
> + img_ver = pkt->data;
>
> dev_dbg(dev, VDBGL "F/W version: %s\n", img_ver);
>
> @@ -277,7 +277,7 @@ static void hfi_sys_property_info(struct venus_core *core,
> return;
> }
>
> - switch (pkt->data[0]) {
> + switch (pkt->property) {
> case HFI_PROPERTY_SYS_IMAGE_VERSION:
> sys_get_prop_image_version(dev, pkt);
> break;
> @@ -338,7 +338,7 @@ session_get_prop_profile_level(struct hfi_msg_session_property_info_pkt *pkt,
> /* bad packet */
> return HFI_ERR_SESSION_INVALID_PARAMETER;
>
> - hfi = (struct hfi_profile_level *)&pkt->data[1];
> + hfi = (struct hfi_profile_level *)&pkt->data[0];
> profile_level->profile = hfi->profile;
> profile_level->level = hfi->level;
>
> @@ -355,11 +355,11 @@ session_get_prop_buf_req(struct hfi_msg_session_property_info_pkt *pkt,
>
> req_bytes = pkt->shdr.hdr.size - sizeof(*pkt);
>
> - if (!req_bytes || req_bytes % sizeof(*buf_req) || !pkt->data[1])
> + if (!req_bytes || req_bytes % sizeof(*buf_req) || !pkt->data[0])
> /* bad packet */
> return HFI_ERR_SESSION_INVALID_PARAMETER;
>
> - buf_req = (struct hfi_buffer_requirements *)&pkt->data[1];
> + buf_req = (struct hfi_buffer_requirements *)&pkt->data[0];
> if (!buf_req)
> return HFI_ERR_SESSION_INVALID_PARAMETER;
>
> @@ -391,7 +391,7 @@ static void hfi_session_prop_info(struct venus_core *core,
> goto done;
> }
>
> - switch (pkt->data[0]) {
> + switch (pkt->property) {
> case HFI_PROPERTY_CONFIG_BUFFER_REQUIREMENTS:
> memset(hprop->bufreq, 0, sizeof(hprop->bufreq));
> error = session_get_prop_buf_req(pkt, hprop->bufreq);
> @@ -404,7 +404,7 @@ static void hfi_session_prop_info(struct venus_core *core,
> case HFI_PROPERTY_CONFIG_VDEC_ENTROPY:
> break;
> default:
> - dev_dbg(dev, VDBGM "unknown property id:%x\n", pkt->data[0]);
> + dev_dbg(dev, VDBGM "unknown property id:%x\n", pkt->property);
> return;
> }
>
> diff --git a/drivers/media/platform/qcom/venus/hfi_msgs.h b/drivers/media/platform/qcom/venus/hfi_msgs.h
> index 526d9f5b487b..510513697335 100644
> --- a/drivers/media/platform/qcom/venus/hfi_msgs.h
> +++ b/drivers/media/platform/qcom/venus/hfi_msgs.h
> @@ -113,7 +113,8 @@ struct hfi_msg_sys_ping_ack_pkt {
> struct hfi_msg_sys_property_info_pkt {
> struct hfi_pkt_hdr hdr;
> u32 num_properties;
> - u32 data[1];
> + u32 property;
> + u8 data[];
> };
>
> struct hfi_msg_session_load_resources_done_pkt {
> @@ -233,7 +234,8 @@ struct hfi_msg_session_parse_sequence_header_done_pkt {
> struct hfi_msg_session_property_info_pkt {
> struct hfi_session_hdr_pkt shdr;
> u32 num_properties;
> - u32 data[1];
> + u32 property;
> + u8 data[];
> };
>
> struct hfi_msg_session_release_resources_done_pkt {
>
