misc: fastrpc: Copy the complete capability structure to user

User is passing capability ioctl structure(argp) to get DSP
capabilities. This argp is copied to a local structure to get domain
and attribute_id information. After getting the capability, only
capability value is getting copied to user argp which will not be
useful if the use is trying to get the capability by checking the
capability member of fastrpc_ioctl_capability structure. Copy the
complete capability structure so that user can get the capability
value from the expected member of the structure.

Fixes: 6c16fd8b ("misc: fastrpc: Add support to get DSP capabilities")
Cc: stable <stable@kernel.org>
Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Caleb Connolly <caleb.connolly@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240628114501.14310-3-srinivas.kandagatla@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/fastrpc.c

@@ -1788,7 +1788,7 @@ static int fastrpc_get_dsp_info(struct fastrpc_user *fl, char __user *argp)
 	if (err)
 		return err;
 
-	if (copy_to_user(argp, &cap.capability, sizeof(cap.capability)))
+	if (copy_to_user(argp, &cap, sizeof(cap)))
 		return -EFAULT;
 
 	return 0;