From: Gustavo A. R. Silva Date: Wed, 7 Sep 2022 18:55:44 +0000 (+0100) Subject: media: usb: pwc-uncompress: Use flex array destination for memcpy() X-Git-Tag: v6.6.7~3400^2~84^2~15 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=389b6a226188c13ec3d5d8b3522aabd68aab2694;p=platform%2Fkernel%2Flinux-starfive.git media: usb: pwc-uncompress: Use flex array destination for memcpy() In preparation for FORTIFY_SOURCE performing run-time destination buffer bounds checking for memcpy(), specify the destination output buffer explicitly, instead of asking memcpy() to write past the end of what looked like a fixed-size object. Notice that raw_frame is a pointer to a structure that contains flexible-array member rawframe[]: drivers/media/usb/pwc/pwc.h: 190 struct pwc_raw_frame { 191 __le16 type; /* type of the webcam */ 192 __le16 vbandlength; /* Size of 4 lines compressed (used by the 193 decompressor) */ 194 __u8 cmd[4]; /* the four byte of the command (in case of 195 nala, only the first 3 bytes is filled) */ 196 __u8 rawframe[]; /* frame_size = H / 4 * vbandlength */ 197 } __packed; Link: https://github.com/KSPP/linux/issues/200 Signed-off-by: Gustavo A. R. Silva Reviewed-by: Kees Cook Signed-off-by: Hans Verkuil --- diff --git a/drivers/media/usb/pwc/pwc-uncompress.c b/drivers/media/usb/pwc/pwc-uncompress.c index faf44cd..cf2591a 100644 --- a/drivers/media/usb/pwc/pwc-uncompress.c +++ b/drivers/media/usb/pwc/pwc-uncompress.c @@ -39,7 +39,7 @@ int pwc_decompress(struct pwc_device *pdev, struct pwc_frame_buf *fbuf) * first 3 bytes is filled (Nala case). We can * determine this using the type of the webcam */ memcpy(raw_frame->cmd, pdev->cmd_buf, 4); - memcpy(raw_frame+1, yuv, pdev->frame_size); + memcpy(raw_frame->rawframe, yuv, pdev->frame_size); vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0, struct_size(raw_frame, rawframe, pdev->frame_size)); return 0;