From 1aa1ec457424fe03c976efda85e062461a44542c Mon Sep 17 00:00:00 2001 From: Kun Qin Date: Wed, 26 Jan 2022 03:39:08 +0800 Subject: ArmPkg: MmCommunicationDxe: Update MM communicate `CommSize` check REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3751 Current MM communicate routine from ArmPkg would conduct few checks prior to proceeding with SMC calls. However, the inspection step is different from PI specification. This patch updated MM communicate input argument inspection routine to assure `CommSize` represents "the size of the data buffer being passed in" instead of the size of the data being used from data buffer, as described by section `EFI_MM_COMMUNICATION2_PROTOCOL.Communicate()` in PI specification. Cc: Leif Lindholm Cc: Ard Biesheuvel Cc: Bret Barkelew Cc: Michael Kubacki Cc: Sami Mujawar Signed-off-by: Kun Qin Reviewed-by: Sami Mujawar --- ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) (limited to 'ArmPkg/Drivers') diff --git a/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c index 0283be430d..2f89b7c5b6 100644 --- a/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c +++ b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c @@ -44,13 +44,18 @@ STATIC EFI_HANDLE mMmCommunicateHandle; @param[in] This The EFI_MM_COMMUNICATION_PROTOCOL instance. @param[in, out] CommBufferPhysical Physical address of the MM communication buffer @param[in, out] CommBufferVirtual Virtual address of the MM communication buffer - @param[in, out] CommSize The size of the data buffer being passed in. On exit, the - size of data being returned. Zero if the handler does not + @param[in, out] CommSize The size of the data buffer being passed in. On input, + when not omitted, the buffer should cover EFI_MM_COMMUNICATE_HEADER + and the value of MessageLength field. On exit, the size + of data being returned. Zero if the handler does not wish to reply with any data. This parameter is optional and may be NULL. @retval EFI_SUCCESS The message was successfully posted. - @retval EFI_INVALID_PARAMETER CommBufferPhysical was NULL or CommBufferVirtual was NULL. + @retval EFI_INVALID_PARAMETER CommBufferPhysical or CommBufferVirtual was NULL, or + integer value pointed by CommSize does not cover + EFI_MM_COMMUNICATE_HEADER and the value of MessageLength + field. @retval EFI_BAD_BUFFER_SIZE The buffer is too large for the MM implementation. If this error is returned, the MessageLength field in the CommBuffer header or the integer pointed by @@ -96,8 +101,8 @@ MmCommunication2Communicate ( sizeof (CommunicateHeader->HeaderGuid) + sizeof (CommunicateHeader->MessageLength); - // If the length of the CommBuffer is 0 then return the expected length. - if (CommSize != 0) { + // If CommSize is not omitted, perform size inspection before proceeding. + if (CommSize != NULL) { // This case can be used by the consumer of this driver to find out the // max size that can be used for allocating CommBuffer. if ((*CommSize == 0) || @@ -108,9 +113,9 @@ MmCommunication2Communicate ( } // - // CommSize must match MessageLength + sizeof (EFI_MM_COMMUNICATE_HEADER); + // CommSize should cover at least MessageLength + sizeof (EFI_MM_COMMUNICATE_HEADER); // - if (*CommSize != BufferSize) { + if (*CommSize < BufferSize) { return EFI_INVALID_PARAMETER; } } -- cgit v1.2.3