From b8e4f1fdfa422398c2d6c47bfb7d1feb3046d70a Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 22 Aug 2019 09:25:27 +0200 Subject: ALSA: usb-audio: Remove superfluous bLength checks Now that we got the more comprehensive validation code for USB-audio descriptors, the check of overflow in each descriptor unit parser became superfluous. Drop some of the obvious cases. Signed-off-by: Takashi Iwai --- sound/usb/clock.c | 14 ++++------ sound/usb/mixer.c | 84 ------------------------------------------------------- 2 files changed, 6 insertions(+), 92 deletions(-) (limited to 'sound/usb') diff --git a/sound/usb/clock.c b/sound/usb/clock.c index 72e9bdf76115..6b8c14f9b5d4 100644 --- a/sound/usb/clock.c +++ b/sound/usb/clock.c @@ -38,39 +38,37 @@ static void *find_uac_clock_desc(struct usb_host_interface *iface, int id, static bool validate_clock_source_v2(void *p, int id) { struct uac_clock_source_descriptor *cs = p; - return cs->bLength == sizeof(*cs) && cs->bClockID == id; + return cs->bClockID == id; } static bool validate_clock_source_v3(void *p, int id) { struct uac3_clock_source_descriptor *cs = p; - return cs->bLength == sizeof(*cs) && cs->bClockID == id; + return cs->bClockID == id; } static bool validate_clock_selector_v2(void *p, int id) { struct uac_clock_selector_descriptor *cs = p; - return cs->bLength >= sizeof(*cs) && cs->bClockID == id && - cs->bLength == 7 + cs->bNrInPins; + return cs->bClockID == id; } static bool validate_clock_selector_v3(void *p, int id) { struct uac3_clock_selector_descriptor *cs = p; - return cs->bLength >= sizeof(*cs) && cs->bClockID == id && - cs->bLength == 11 + cs->bNrInPins; + return cs->bClockID == id; } static bool validate_clock_multiplier_v2(void *p, int id) { struct uac_clock_multiplier_descriptor *cs = p; - return cs->bLength == sizeof(*cs) && cs->bClockID == id; + return cs->bClockID == id; } static bool validate_clock_multiplier_v3(void *p, int id) { struct uac3_clock_multiplier_descriptor *cs = p; - return cs->bLength == sizeof(*cs) && cs->bClockID == id; + return cs->bClockID == id; } #define DEFINE_FIND_HELPER(name, obj, validator, type) \ diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index 277660fd6e0a..c9777d8a76f5 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -740,13 +740,6 @@ static int uac_mixer_unit_get_channels(struct mixer_build *state, { int mu_channels; - if (desc->bLength < sizeof(*desc)) - return -EINVAL; - if (!desc->bNrInPins) - return -EINVAL; - if (desc->bLength < sizeof(*desc) + desc->bNrInPins) - return -EINVAL; - switch (state->mixer->protocol) { case UAC_VERSION_1: case UAC_VERSION_2: @@ -1781,13 +1774,6 @@ static int parse_clock_source_unit(struct mixer_build *state, int unitid, if (state->mixer->protocol != UAC_VERSION_2) return -EINVAL; - if (hdr->bLength != sizeof(*hdr)) { - usb_audio_dbg(state->chip, - "Bogus clock source descriptor length of %d, ignoring.\n", - hdr->bLength); - return 0; - } - /* * The only property of this unit we are interested in is the * clock source validity. If that isn't readable, just bail out. @@ -1846,62 +1832,20 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid, __u8 *bmaControls; if (state->mixer->protocol == UAC_VERSION_1) { - if (hdr->bLength < 7) { - usb_audio_err(state->chip, - "unit %u: invalid UAC_FEATURE_UNIT descriptor\n", - unitid); - return -EINVAL; - } csize = hdr->bControlSize; - if (!csize) { - usb_audio_dbg(state->chip, - "unit %u: invalid bControlSize == 0\n", - unitid); - return -EINVAL; - } channels = (hdr->bLength - 7) / csize - 1; bmaControls = hdr->bmaControls; - if (hdr->bLength < 7 + csize) { - usb_audio_err(state->chip, - "unit %u: invalid UAC_FEATURE_UNIT descriptor\n", - unitid); - return -EINVAL; - } } else if (state->mixer->protocol == UAC_VERSION_2) { struct uac2_feature_unit_descriptor *ftr = _ftr; - if (hdr->bLength < 6) { - usb_audio_err(state->chip, - "unit %u: invalid UAC_FEATURE_UNIT descriptor\n", - unitid); - return -EINVAL; - } csize = 4; channels = (hdr->bLength - 6) / 4 - 1; bmaControls = ftr->bmaControls; - if (hdr->bLength < 6 + csize) { - usb_audio_err(state->chip, - "unit %u: invalid UAC_FEATURE_UNIT descriptor\n", - unitid); - return -EINVAL; - } } else { /* UAC_VERSION_3 */ struct uac3_feature_unit_descriptor *ftr = _ftr; - if (hdr->bLength < 7) { - usb_audio_err(state->chip, - "unit %u: invalid UAC3_FEATURE_UNIT descriptor\n", - unitid); - return -EINVAL; - } csize = 4; channels = (ftr->bLength - 7) / 4 - 1; bmaControls = ftr->bmaControls; - if (hdr->bLength < 7 + csize) { - usb_audio_err(state->chip, - "unit %u: invalid UAC3_FEATURE_UNIT descriptor\n", - unitid); - return -EINVAL; - } } /* parse the source unit */ @@ -2101,15 +2045,11 @@ static int parse_audio_input_terminal(struct mixer_build *state, int unitid, if (state->mixer->protocol == UAC_VERSION_2) { struct uac2_input_terminal_descriptor *d_v2 = raw_desc; - if (d_v2->bLength < sizeof(*d_v2)) - return -EINVAL; control = UAC2_TE_CONNECTOR; term_id = d_v2->bTerminalID; bmctls = le16_to_cpu(d_v2->bmControls); } else if (state->mixer->protocol == UAC_VERSION_3) { struct uac3_input_terminal_descriptor *d_v3 = raw_desc; - if (d_v3->bLength < sizeof(*d_v3)) - return -EINVAL; control = UAC3_TE_INSERTION; term_id = d_v3->bTerminalID; bmctls = le32_to_cpu(d_v3->bmControls); @@ -2371,18 +2311,7 @@ static int build_audio_procunit(struct mixer_build *state, int unitid, const char *name = extension_unit ? "Extension Unit" : "Processing Unit"; - if (desc->bLength < 13) { - usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid); - return -EINVAL; - } - num_ins = desc->bNrInPins; - if (desc->bLength < 13 + num_ins || - desc->bLength < num_ins + uac_processing_unit_bControlSize(desc, state->mixer->protocol)) { - usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid); - return -EINVAL; - } - for (i = 0; i < num_ins; i++) { err = parse_audio_unit(state, desc->baSourceID[i]); if (err < 0) @@ -2637,13 +2566,6 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid, const struct usbmix_name_map *map; char **namelist; - if (desc->bLength < 5 || !desc->bNrInPins || - desc->bLength < 5 + desc->bNrInPins) { - usb_audio_err(state->chip, - "invalid SELECTOR UNIT descriptor %d\n", unitid); - return -EINVAL; - } - for (i = 0; i < desc->bNrInPins; i++) { err = parse_audio_unit(state, desc->baSourceID[i]); if (err < 0) @@ -3149,8 +3071,6 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer) if (mixer->protocol == UAC_VERSION_1) { struct uac1_output_terminal_descriptor *desc = p; - if (desc->bLength < sizeof(*desc)) - continue; /* invalid descriptor? */ /* mark terminal ID as visited */ set_bit(desc->bTerminalID, state.unitbitmap); state.oterm.id = desc->bTerminalID; @@ -3162,8 +3082,6 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer) } else if (mixer->protocol == UAC_VERSION_2) { struct uac2_output_terminal_descriptor *desc = p; - if (desc->bLength < sizeof(*desc)) - continue; /* invalid descriptor? */ /* mark terminal ID as visited */ set_bit(desc->bTerminalID, state.unitbitmap); state.oterm.id = desc->bTerminalID; @@ -3189,8 +3107,6 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer) } else { /* UAC_VERSION_3 */ struct uac3_output_terminal_descriptor *desc = p; - if (desc->bLength < sizeof(*desc)) - continue; /* invalid descriptor? */ /* mark terminal ID as visited */ set_bit(desc->bTerminalID, state.unitbitmap); state.oterm.id = desc->bTerminalID; -- cgit v1.2.3