From: Ruslan Bilovol <ruslan.bilovol@xxxxxxxxx> [ Upstream commit 3713d5ceb04d5ab6a5e2b86dfca49170053f3a5e ] Currently user can configure UAC2 function with parameters that violate UAC2 spec or are not supported by UAC2 gadget implementation. This can lead to incorrect behavior if such gadget is connected to the host - like enumeration failure or other issues depending on host's UAC2 driver implementation, bringing user to a long hours of debugging the issue. Instead of silently accept these parameters, throw an error if they are not valid. Signed-off-by: Ruslan Bilovol <ruslan.bilovol@xxxxxxxxx> Link: https://lore.kernel.org/r/1614599375-8803-4-git-send-email-ruslan.bilovol@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/usb/gadget/function/f_uac2.c | 39 ++++++++++++++++++++++++++-- 1 file changed, 37 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c index 6f03e944e0e3..dd960cea642f 100644 --- a/drivers/usb/gadget/function/f_uac2.c +++ b/drivers/usb/gadget/function/f_uac2.c @@ -14,6 +14,9 @@ #include "u_audio.h" #include "u_uac2.h" +/* UAC2 spec: 4.1 Audio Channel Cluster Descriptor */ +#define UAC2_CHANNEL_MASK 0x07FFFFFF + /* * The driver implements a simple UAC_2 topology. * USB-OUT -> IT_1 -> OT_3 -> ALSA_Capture @@ -604,6 +607,36 @@ static void setup_descriptor(struct f_uac2_opts *opts) hs_audio_desc[i] = NULL; } +static int afunc_validate_opts(struct g_audio *agdev, struct device *dev) +{ + struct f_uac2_opts *opts = g_audio_to_uac2_opts(agdev); + + if (!opts->p_chmask && !opts->c_chmask) { + dev_err(dev, "Error: no playback and capture channels\n"); + return -EINVAL; + } else if (opts->p_chmask & ~UAC2_CHANNEL_MASK) { + dev_err(dev, "Error: unsupported playback channels mask\n"); + return -EINVAL; + } else if (opts->c_chmask & ~UAC2_CHANNEL_MASK) { + dev_err(dev, "Error: unsupported capture channels mask\n"); + return -EINVAL; + } else if ((opts->p_ssize < 1) || (opts->p_ssize > 4)) { + dev_err(dev, "Error: incorrect playback sample size\n"); + return -EINVAL; + } else if ((opts->c_ssize < 1) || (opts->c_ssize > 4)) { + dev_err(dev, "Error: incorrect capture sample size\n"); + return -EINVAL; + } else if (!opts->p_srate) { + dev_err(dev, "Error: incorrect playback sampling rate\n"); + return -EINVAL; + } else if (!opts->c_srate) { + dev_err(dev, "Error: incorrect capture sampling rate\n"); + return -EINVAL; + } + + return 0; +} + static int afunc_bind(struct usb_configuration *cfg, struct usb_function *fn) { @@ -612,11 +645,13 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn) struct usb_composite_dev *cdev = cfg->cdev; struct usb_gadget *gadget = cdev->gadget; struct device *dev = &gadget->dev; - struct f_uac2_opts *uac2_opts; + struct f_uac2_opts *uac2_opts = g_audio_to_uac2_opts(agdev); struct usb_string *us; int ret; - uac2_opts = container_of(fn->fi, struct f_uac2_opts, func_inst); + ret = afunc_validate_opts(agdev, dev); + if (ret) + return ret; us = usb_gstrings_attach(cdev, fn_strings, ARRAY_SIZE(strings_fn)); if (IS_ERR(us)) -- 2.30.2
