From: Takashi Iwai Date: Thu, 14 Aug 2025 08:12:42 +0000 (+0200) Subject: ALSA: usb-audio: Validate UAC3 power domain descriptors, too X-Git-Tag: v6.16.2~560 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=452ad54f432675982cc0d6eb6c40a6c86ac61dbd;p=thirdparty%2Fkernel%2Fstable.git ALSA: usb-audio: Validate UAC3 power domain descriptors, too commit d832ccbc301fbd9e5a1d691bdcf461cdb514595f upstream. UAC3 power domain descriptors need to be verified with its variable bLength for avoiding the unexpected OOB accesses by malicious firmware, too. Fixes: 9a2fe9b801f5 ("ALSA: usb: initial USB Audio Device Class 3.0 support") Reported-and-tested-by: Youngjun Lee Cc: Link: https://patch.msgid.link/20250814081245.8902-1-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- diff --git a/sound/usb/validate.c b/sound/usb/validate.c index 6fe206f6e9110..4f4e8e87a14cd 100644 --- a/sound/usb/validate.c +++ b/sound/usb/validate.c @@ -221,6 +221,17 @@ static bool validate_uac3_feature_unit(const void *p, return d->bLength >= sizeof(*d) + 4 + 2; } +static bool validate_uac3_power_domain_unit(const void *p, + const struct usb_desc_validator *v) +{ + const struct uac3_power_domain_descriptor *d = p; + + if (d->bLength < sizeof(*d)) + return false; + /* baEntities[] + wPDomainDescrStr */ + return d->bLength >= sizeof(*d) + d->bNrEntities + 2; +} + static bool validate_midi_out_jack(const void *p, const struct usb_desc_validator *v) { @@ -285,6 +296,7 @@ static const struct usb_desc_validator audio_validators[] = { struct uac3_clock_multiplier_descriptor), /* UAC_VERSION_3, UAC3_SAMPLE_RATE_CONVERTER: not implemented yet */ /* UAC_VERSION_3, UAC3_CONNECTORS: not implemented yet */ + FUNC(UAC_VERSION_3, UAC3_POWER_DOMAIN, validate_uac3_power_domain_unit), { } /* terminator */ };