Hi, Evgenv Thanks for your contribution, Evgenv
Could you let me know what error case you met? Is the Device Desc or Config Desc larger than expected or other descs? Why I ask this question is because it would impact Xhci driver's implementation in which we store some desc contents at internal. So looks like XHCI driver also needs to be updated. Thanks Feng -----Original Message----- From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of Evgeny Yakovlev Sent: Sunday, June 5, 2016 10:29 PM To: edk2-devel@lists.01.org Subject: [edk2] [PATCH] MdeModulePkg/UsbBusDxe: Fixed USB descriptor length check According to spec if the length of a descriptor is smaller than what the specification defines, then the host shall ignore it. However if the size is greater than expected the host will ignore the extra bytes and start looking for the next descriptor at the end of actual length returned. Original check did not handle the latter case correctly and only allowed descriptors with lengths exactly as defined in specification. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Evgeny Yakovlev <insorei...@gmail.com> --- MdeModulePkg/Bus/Usb/UsbBusDxe/UsbDesc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbDesc.c b/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbDesc.c index 5b8b1aa..fba60da 100644 --- a/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbDesc.c +++ b/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbDesc.c @@ -199,8 +199,8 @@ UsbCreateDesc ( } } - if ((Len <= Offset) || (Len < Offset + DescLen) || - (Head->Type != Type) || (Head->Len != DescLen)) { + if ((Len <= Offset) || (Len < Offset + Head->Len) || + (Head->Type != Type) || (Head->Len < DescLen)) { DEBUG (( EFI_D_ERROR, "UsbCreateDesc: met mal-format descriptor\n")); return NULL; } -- 2.7.4 (Apple Git-66) _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
