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Diffstat (limited to '')
| -rw-r--r-- | sound/usb/validate.c | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/sound/usb/validate.c b/sound/usb/validate.c new file mode 100644 index 000000000..6fe206f6e --- /dev/null +++ b/sound/usb/validate.c @@ -0,0 +1,349 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +// +// Validation of USB-audio class descriptors +// + +#include <linux/init.h> +#include <linux/usb.h> +#include <linux/usb/audio.h> +#include <linux/usb/audio-v2.h> +#include <linux/usb/audio-v3.h> +#include <linux/usb/midi.h> +#include "usbaudio.h" +#include "helper.h" + +struct usb_desc_validator { + unsigned char protocol; + unsigned char type; + bool (*func)(const void *p, const struct usb_desc_validator *v); + size_t size; +}; + +#define UAC_VERSION_ALL (unsigned char)(-1) + +/* UAC1 only */ +static bool validate_uac1_header(const void *p, + const struct usb_desc_validator *v) +{ + const struct uac1_ac_header_descriptor *d = p; + + return d->bLength >= sizeof(*d) && + d->bLength >= sizeof(*d) + d->bInCollection; +} + +/* for mixer unit; covering all UACs */ +static bool validate_mixer_unit(const void *p, + const struct usb_desc_validator *v) +{ + const struct uac_mixer_unit_descriptor *d = p; + size_t len; + + if (d->bLength < sizeof(*d) || !d->bNrInPins) + return false; + len = sizeof(*d) + d->bNrInPins; + /* We can't determine the bitmap size only from this unit descriptor, + * so just check with the remaining length. + * The actual bitmap is checked at mixer unit parser. + */ + switch (v->protocol) { + case UAC_VERSION_1: + default: + len += 2 + 1; /* wChannelConfig, iChannelNames */ + /* bmControls[n*m] */ + len += 1; /* iMixer */ + break; + case UAC_VERSION_2: + len += 4 + 1; /* bmChannelConfig, iChannelNames */ + /* bmMixerControls[n*m] */ + len += 1 + 1; /* bmControls, iMixer */ + break; + case UAC_VERSION_3: + len += 2; /* wClusterDescrID */ + /* bmMixerControls[n*m] */ + break; + } + return d->bLength >= len; +} + +/* both for processing and extension units; covering all UACs */ +static bool validate_processing_unit(const void *p, + const struct usb_desc_validator *v) +{ + const struct uac_processing_unit_descriptor *d = p; + const unsigned char *hdr = p; + size_t len, m; + + if (d->bLength < sizeof(*d)) + return false; + len = sizeof(*d) + d->bNrInPins; + if (d->bLength < len) + return false; + switch (v->protocol) { + case UAC_VERSION_1: + default: + /* bNrChannels, wChannelConfig, iChannelNames */ + len += 1 + 2 + 1; + if (d->bLength < len + 1) /* bControlSize */ + return false; + m = hdr[len]; + len += 1 + m + 1; /* bControlSize, bmControls, iProcessing */ + break; + case UAC_VERSION_2: + /* bNrChannels, bmChannelConfig, iChannelNames */ + len += 1 + 4 + 1; + if (v->type == UAC2_PROCESSING_UNIT_V2) + len += 2; /* bmControls -- 2 bytes for PU */ + else + len += 1; /* bmControls -- 1 byte for EU */ + len += 1; /* iProcessing */ + break; + case UAC_VERSION_3: + /* wProcessingDescrStr, bmControls */ + len += 2 + 4; + break; + } + if (d->bLength < len) + return false; + + switch (v->protocol) { + case UAC_VERSION_1: + default: + if (v->type == UAC1_EXTENSION_UNIT) + return true; /* OK */ + switch (le16_to_cpu(d->wProcessType)) { + case UAC_PROCESS_UP_DOWNMIX: + case UAC_PROCESS_DOLBY_PROLOGIC: + if (d->bLength < len + 1) /* bNrModes */ + return false; + m = hdr[len]; + len += 1 + m * 2; /* bNrModes, waModes(n) */ + break; + default: + break; + } + break; + case UAC_VERSION_2: + if (v->type == UAC2_EXTENSION_UNIT_V2) + return true; /* OK */ + switch (le16_to_cpu(d->wProcessType)) { + case UAC2_PROCESS_UP_DOWNMIX: + case UAC2_PROCESS_DOLBY_PROLOCIC: /* SiC! */ + if (d->bLength < len + 1) /* bNrModes */ + return false; + m = hdr[len]; + len += 1 + m * 4; /* bNrModes, daModes(n) */ + break; + default: + break; + } + break; + case UAC_VERSION_3: + if (v->type == UAC3_EXTENSION_UNIT) { + len += 2; /* wClusterDescrID */ + break; + } + switch (le16_to_cpu(d->wProcessType)) { + case UAC3_PROCESS_UP_DOWNMIX: + if (d->bLength < len + 1) /* bNrModes */ + return false; + m = hdr[len]; + len += 1 + m * 2; /* bNrModes, waClusterDescrID(n) */ + break; + case UAC3_PROCESS_MULTI_FUNCTION: + len += 2 + 4; /* wClusterDescrID, bmAlgorighms */ + break; + default: + break; + } + break; + } + if (d->bLength < len) + return false; + + return true; +} + +/* both for selector and clock selector units; covering all UACs */ +static bool validate_selector_unit(const void *p, + const struct usb_desc_validator *v) +{ + const struct uac_selector_unit_descriptor *d = p; + size_t len; + + if (d->bLength < sizeof(*d)) + return false; + len = sizeof(*d) + d->bNrInPins; + switch (v->protocol) { + case UAC_VERSION_1: + default: + len += 1; /* iSelector */ + break; + case UAC_VERSION_2: + len += 1 + 1; /* bmControls, iSelector */ + break; + case UAC_VERSION_3: + len += 4 + 2; /* bmControls, wSelectorDescrStr */ + break; + } + return d->bLength >= len; +} + +static bool validate_uac1_feature_unit(const void *p, + const struct usb_desc_validator *v) +{ + const struct uac_feature_unit_descriptor *d = p; + + if (d->bLength < sizeof(*d) || !d->bControlSize) + return false; + /* at least bmaControls(0) for master channel + iFeature */ + return d->bLength >= sizeof(*d) + d->bControlSize + 1; +} + +static bool validate_uac2_feature_unit(const void *p, + const struct usb_desc_validator *v) +{ + const struct uac2_feature_unit_descriptor *d = p; + + if (d->bLength < sizeof(*d)) + return false; + /* at least bmaControls(0) for master channel + iFeature */ + return d->bLength >= sizeof(*d) + 4 + 1; +} + +static bool validate_uac3_feature_unit(const void *p, + const struct usb_desc_validator *v) +{ + const struct uac3_feature_unit_descriptor *d = p; + + if (d->bLength < sizeof(*d)) + return false; + /* at least bmaControls(0) for master channel + wFeatureDescrStr */ + return d->bLength >= sizeof(*d) + 4 + 2; +} + +static bool validate_midi_out_jack(const void *p, + const struct usb_desc_validator *v) +{ + const struct usb_midi_out_jack_descriptor *d = p; + + return d->bLength >= sizeof(*d) && + d->bLength >= sizeof(*d) + d->bNrInputPins * 2; +} + +#define FIXED(p, t, s) { .protocol = (p), .type = (t), .size = sizeof(s) } +#define FUNC(p, t, f) { .protocol = (p), .type = (t), .func = (f) } + +static const struct usb_desc_validator audio_validators[] = { + /* UAC1 */ + FUNC(UAC_VERSION_1, UAC_HEADER, validate_uac1_header), + FIXED(UAC_VERSION_1, UAC_INPUT_TERMINAL, + struct uac_input_terminal_descriptor), + FIXED(UAC_VERSION_1, UAC_OUTPUT_TERMINAL, + struct uac1_output_terminal_descriptor), + FUNC(UAC_VERSION_1, UAC_MIXER_UNIT, validate_mixer_unit), + FUNC(UAC_VERSION_1, UAC_SELECTOR_UNIT, validate_selector_unit), + FUNC(UAC_VERSION_1, UAC_FEATURE_UNIT, validate_uac1_feature_unit), + FUNC(UAC_VERSION_1, UAC1_PROCESSING_UNIT, validate_processing_unit), + FUNC(UAC_VERSION_1, UAC1_EXTENSION_UNIT, validate_processing_unit), + + /* UAC2 */ + FIXED(UAC_VERSION_2, UAC_HEADER, struct uac2_ac_header_descriptor), + FIXED(UAC_VERSION_2, UAC_INPUT_TERMINAL, + struct uac2_input_terminal_descriptor), + FIXED(UAC_VERSION_2, UAC_OUTPUT_TERMINAL, + struct uac2_output_terminal_descriptor), + FUNC(UAC_VERSION_2, UAC_MIXER_UNIT, validate_mixer_unit), + FUNC(UAC_VERSION_2, UAC_SELECTOR_UNIT, validate_selector_unit), + FUNC(UAC_VERSION_2, UAC_FEATURE_UNIT, validate_uac2_feature_unit), + /* UAC_VERSION_2, UAC2_EFFECT_UNIT: not implemented yet */ + FUNC(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2, validate_processing_unit), + FUNC(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2, validate_processing_unit), + FIXED(UAC_VERSION_2, UAC2_CLOCK_SOURCE, + struct uac_clock_source_descriptor), + FUNC(UAC_VERSION_2, UAC2_CLOCK_SELECTOR, validate_selector_unit), + FIXED(UAC_VERSION_2, UAC2_CLOCK_MULTIPLIER, + struct uac_clock_multiplier_descriptor), + /* UAC_VERSION_2, UAC2_SAMPLE_RATE_CONVERTER: not implemented yet */ + + /* UAC3 */ + FIXED(UAC_VERSION_2, UAC_HEADER, struct uac3_ac_header_descriptor), + FIXED(UAC_VERSION_3, UAC_INPUT_TERMINAL, + struct uac3_input_terminal_descriptor), + FIXED(UAC_VERSION_3, UAC_OUTPUT_TERMINAL, + struct uac3_output_terminal_descriptor), + /* UAC_VERSION_3, UAC3_EXTENDED_TERMINAL: not implemented yet */ + FUNC(UAC_VERSION_3, UAC3_MIXER_UNIT, validate_mixer_unit), + FUNC(UAC_VERSION_3, UAC3_SELECTOR_UNIT, validate_selector_unit), + FUNC(UAC_VERSION_3, UAC_FEATURE_UNIT, validate_uac3_feature_unit), + /* UAC_VERSION_3, UAC3_EFFECT_UNIT: not implemented yet */ + FUNC(UAC_VERSION_3, UAC3_PROCESSING_UNIT, validate_processing_unit), + FUNC(UAC_VERSION_3, UAC3_EXTENSION_UNIT, validate_processing_unit), + FIXED(UAC_VERSION_3, UAC3_CLOCK_SOURCE, + struct uac3_clock_source_descriptor), + FUNC(UAC_VERSION_3, UAC3_CLOCK_SELECTOR, validate_selector_unit), + FIXED(UAC_VERSION_3, UAC3_CLOCK_MULTIPLIER, + struct uac3_clock_multiplier_descriptor), + /* UAC_VERSION_3, UAC3_SAMPLE_RATE_CONVERTER: not implemented yet */ + /* UAC_VERSION_3, UAC3_CONNECTORS: not implemented yet */ + { } /* terminator */ +}; + +static const struct usb_desc_validator midi_validators[] = { + FIXED(UAC_VERSION_ALL, USB_MS_HEADER, + struct usb_ms_header_descriptor), + FIXED(UAC_VERSION_ALL, USB_MS_MIDI_IN_JACK, + struct usb_midi_in_jack_descriptor), + FUNC(UAC_VERSION_ALL, USB_MS_MIDI_OUT_JACK, + validate_midi_out_jack), + { } /* terminator */ +}; + + +/* Validate the given unit descriptor, return true if it's OK */ +static bool validate_desc(unsigned char *hdr, int protocol, + const struct usb_desc_validator *v) +{ + if (hdr[1] != USB_DT_CS_INTERFACE) + return true; /* don't care */ + + for (; v->type; v++) { + if (v->type == hdr[2] && + (v->protocol == UAC_VERSION_ALL || + v->protocol == protocol)) { + if (v->func) + return v->func(hdr, v); + /* check for the fixed size */ + return hdr[0] >= v->size; + } + } + + return true; /* not matching, skip validation */ +} + +bool snd_usb_validate_audio_desc(void *p, int protocol) +{ + unsigned char *c = p; + bool valid; + + valid = validate_desc(p, protocol, audio_validators); + if (!valid && snd_usb_skip_validation) { + print_hex_dump(KERN_ERR, "USB-audio: buggy audio desc: ", + DUMP_PREFIX_NONE, 16, 1, c, c[0], true); + valid = true; + } + return valid; +} + +bool snd_usb_validate_midi_desc(void *p) +{ + unsigned char *c = p; + bool valid; + + valid = validate_desc(p, UAC_VERSION_1, midi_validators); + if (!valid && snd_usb_skip_validation) { + print_hex_dump(KERN_ERR, "USB-audio: buggy midi desc: ", + DUMP_PREFIX_NONE, 16, 1, c, c[0], true); + valid = true; + } + return valid; +} |