mirror of https://github.com/acidanthera/audk.git
cf574f0a18
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1136 CVE: CVE-2018-12182 Customer met system hang-up during serial port loopback test in OS. It is a corner case happened with one CPU core doing "out dx,al" and another CPU core(s) doing "rep outs dx,byte ptr [rsi]". Detailed code flow is as below. 1. Serial port loopback test in OS. One CPU core: "out dx,al" -> Writing B2h, SMI will happen. Another CPU core(s): "rep outs dx,byte ptr [rsi]". 2. SMI happens to enter SMM. "out dx" (SMM_IO_TYPE_OUT_DX) is saved as I/O instruction type in SMRAM save state for CPU doing "out dx,al". "rep outs dx" (SMM_IO_TYPE_REP_OUTS) is saved as I/O instruction type and rsi is save as I/O Memory Address in SMRAM save state for CPU doing "rep outs dx, byte ptr [rsi]". NOTE: I/O Memory Address (rsi) is a virtual address mapped by OS/Virtual Machine. 3. Some SMM code calls EFI_SMM_CPU_PROTOCOL.ReadSaveState() with EFI_SMM_SAVE_STATE_REGISTER_IO and parse data returned. For example: https://github.com/tianocore/edk2/blob/master/QuarkSocPkg/ QuarkNorthCluster/Smm/DxeSmm/QncSmmDispatcher/QNC/QNCSmmSw.c#L76 4. SmmReadSaveState() is executed to read save state for EFI_SMM_SAVE_STATE_REGISTER_IO. - The SmmReadSaveState() function in "UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c" calls the SmmCpuFeaturesReadSaveStateRegister() function, from the platform's SmmCpuFeaturesLib instance. - If that platform-specific function returns EFI_UNSUPPORTED, then PiSmmCpuDxeSmm falls back to the common function ReadSaveStateRegister(), defined in file "UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c". Current ReadSaveStateRegister() in UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c is trying to copy data from I/O Memory Address for EFI_SMM_SAVE_STATE_IO_TYPE_REP_PREFIX, PF will happen as SMM page table does not know and cover this OS/Virtual Machine virtual address. Same case is for SmmCpuFeaturesReadSaveStateRegister() in platform- specific SmmCpuFeaturesLib instance if it has similar implementation to read save state for EFI_SMM_SAVE_STATE_REGISTER_IO with EFI_SMM_SAVE_STATE_IO_TYPE_REP_PREFIX. Same case is for "ins", 'outs' and 'rep ins'. So to fix the problem, this patch updates the code to only support IN/OUT, but not INS/OUTS/REP INS/REP OUTS for SmmReadSaveState(). Cc: Eric Dong <eric.dong@intel.com> Cc: Ray Ni <ray.ni@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Star Zeng <star.zeng@intel.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> |
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| .. | ||
| Ia32 | ||
| X64 | ||
| CpuS3.c | ||
| CpuService.c | ||
| CpuService.h | ||
| MpService.c | ||
| PiSmmCpuDxeSmm.c | ||
| PiSmmCpuDxeSmm.h | ||
| PiSmmCpuDxeSmm.inf | ||
| PiSmmCpuDxeSmm.uni | ||
| PiSmmCpuDxeSmmExtra.uni | ||
| SmmCpuMemoryManagement.c | ||
| SmmProfile.c | ||
| SmmProfile.h | ||
| SmmProfileInternal.h | ||
| SmramSaveState.c | ||
| SyncTimer.c | ||