Hi Jiewen, "Yao, Jiewen" <jiewen....@intel.com> writes:
> I have some more thought on #3 for your consideration. > > Given the situation that we are doing heap guard feature, a *valid* > EIP address might not be enough to guarantee the address is inside of > an *executable* page. OK. > > I am thinking if we need check the non-executable bit (BIT63) as well for > DumpImageModuleNames(). (No need for DumpStacktrace()). > We can add IsLogicalAddressExecutable() on top of > IsLogicalAddressValid(). OK. I can do that. > Also I do not object the idea to add check inside of PeCoffSearchImageBase(). > I am thinking in another way - we can let *caller* to input a validation > function for the PeCoffLib, instead of let PeCoffLib depend on another > library. > > For example: > PeCoffSearchImageBaseEx (Address, ValidateAddressFunc) Looks good to me! Whether or not we're making it into a external library in the future, we should at least get it working and well tested for the stack trace support. Thanks! Paulo >> -----Original Message----- >> From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of Yao, >> Jiewen >> Sent: Wednesday, January 17, 2018 8:57 PM >> To: Paulo Alcantara <pa...@paulo.ac>; edk2-devel@lists.01.org >> Cc: Rick Bramley <richard.bram...@hp.com>; Dong, Eric >> <eric.d...@intel.com>; Kimon Berlin <kimon.ber...@hp.com>; Andrew Fish >> <af...@apple.com>; Diego Medaglia <diego.meag...@hp.com>; Laszlo Ersek >> <ler...@redhat.com> >> Subject: Re: [edk2] [RFC v5 0/8] Stack trace support in X64 exception >> handling >> >> Thanks Paulo. >> >> The series looks really good. I give it thumb up. :-) >> >> The 8 patches keep updating 4 files, so I squash them when I review. The >> comment below is for the final code, not for a specific patch. >> >> 1) CpuExceptionCommon.c: IsLinearAddressRangeValid(). >> // >> // Check for valid input parameters >> // >> if (LinearAddressStart == 0 || LinearAddressEnd == 0 || >> LinearAddressStart > LinearAddressEnd) { >> return FALSE; >> } >> >> I think LinearAddressStart is a valid case. In BIOS, we do update IVT in 0 >> address >> when CSM is enabled. >> I do not think we need exclude it here. If we enabled ZeroPointer >> protection, it >> can be excluded in page table parsing. >> >> 2) I found below logic appears in 2 functions - DumpImageModuleNames() and >> DumpStacktrace(). Is that possible to merge them? >> We can calculate in DumpImageAndCpuContent() and use Eip as parameter. Just >> in case there is 3rd function need use EIP, it won't miss the calculation. >> (It is a bug fix we did recently.) >> >> // >> // Set current EIP address >> // >> if ((ExceptionType == EXCEPT_IA32_PAGE_FAULT) && >> ((SystemContext.SystemContextIa32->ExceptionData & >> IA32_PF_EC_ID) != 0)) { >> // >> // The EIP in SystemContext could not be used >> // if it is page fault with I/D set. >> // >> Eip = *(UINT32 *)(UINTN)SystemContext.SystemContextIa32->Esp; >> } else { >> Eip = SystemContext.SystemContextIa32->Eip; >> } >> >> 3) I am a little surprised on PeCoffSearchImageBase() issue. >> >> We have 4 PeCoffSearchImageBase() call in each arch. >> DumpImageModuleNames() calls twice and DumpStacktrace() calls twice. >> Do you know which specific one triggers the zero address #PF issue? >> >> >> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\CpuExceptionHandlerLib\Ia32\Arch >> ExceptionHandler.c(547): ImageBase = PeCoffSearchImageBase (Eip); >> >> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\CpuExceptionHandlerLib\Ia32\Arch >> ExceptionHandler.c(613): ImageBase = PeCoffSearchImageBase (Eip); >> >> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\CpuExceptionHandlerLib\Ia32\Arch >> ExceptionHandler.c(682): ImageBase = PeCoffSearchImageBase (Eip); >> >> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\CpuExceptionHandlerLib\Ia32\Arch >> ExceptionHandler.c(741): ImageBase = PeCoffSearchImageBase (Eip); >> >> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\CpuExceptionHandlerLib\X64\Arch >> ExceptionHandler.c(540): ImageBase = PeCoffSearchImageBase (Rip); >> >> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\CpuExceptionHandlerLib\X64\Arch >> ExceptionHandler.c(613): ImageBase = PeCoffSearchImageBase (Rip); >> >> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\CpuExceptionHandlerLib\X64\Arch >> ExceptionHandler.c(710): ImageBase = PeCoffSearchImageBase (Rip); >> >> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\CpuExceptionHandlerLib\X64\Arch >> ExceptionHandler.c(779): ImageBase = PeCoffSearchImageBase (Rip); >> >> The EIP from SystemContext seems good. I assume there is not a problem here. >> >> if ((ExceptionType == EXCEPT_IA32_PAGE_FAULT) && >> ((SystemContext.SystemContextIa32->ExceptionData & >> IA32_PF_EC_ID) != 0)) { >> // >> // The EIP in SystemContext could not be used >> // if it is page fault with I/D set. >> // >> Eip = *(UINT32 *)(UINTN)SystemContext.SystemContextIa32->Esp; >> } else { >> Eip = SystemContext.SystemContextIa32->Eip; >> } >> >> // >> // Get initial PE/COFF image base address from current EIP >> // >> ImageBase = PeCoffSearchImageBase (Eip); >> >> But the EIP from stack frame is unknown and risky. Especially for the code in >> mode-switch, such as PEI->DXE, UEFI->CSM, AP wakeup->AP C code, SMM >> entrypoint->SMM C code. >> Should we add a check for EIP here? >> >> // >> // Set EIP with return address from current stack frame >> // >> Eip = *(UINT32 *)((UINTN)Ebp + 4); >> >> // >> // If EIP is zero, then stop unwinding the stack >> // >> if (Eip == 0) { >> break; >> } >> >> // >> // Search for the respective PE/COFF image based on EIP >> // >> ImageBase = PeCoffSearchImageBase (Eip); >> >> If you can help us do some more investigation on the root-cause and narrow >> down the issue, I will appreciate that. >> >> We can decide how to fix once it is root-caused. >> >> Maybe we just do a simple IsLogicalAddressValid () check before we call >> PeCoffSearchImageBase(). :-) >> >> >> Thank you >> Yao Jiewen >> >> > -----Original Message----- >> > From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of >> Paulo >> > Alcantara >> > Sent: Monday, January 15, 2018 8:23 AM >> > To: edk2-devel@lists.01.org >> > Cc: Rick Bramley <richard.bram...@hp.com>; Dong, Eric >> > <eric.d...@intel.com>; Kimon Berlin <kimon.ber...@hp.com>; Andrew Fish >> > <af...@apple.com>; Yao, Jiewen <jiewen....@intel.com>; Diego Medaglia >> > <diego.meag...@hp.com>; Laszlo Ersek <ler...@redhat.com> >> > Subject: [edk2] [RFC v5 0/8] Stack trace support in X64 exception handling >> > >> > Hi, >> > >> > This series adds stack trace support during IA32 and X64 CPU exceptions. >> > >> > Informations like back trace, stack contents and image module names >> > (that were part of the call stack) will be dumped out. >> > >> > The current limitation is that it relies on available frame pointers >> > (GCC only) in order to successfully unwind the stack. >> > >> > Jiewen, >> > >> > Thank you very much for your time on this. I've applied the changes you >> > suggested, as well as tested it on IA32 PAE paging mode - it worked as >> > expected. >> > >> > Other than that, I also tested the stack trace in SMM code by manually >> > calling CpuBreakPoint() and then it broke with another exception >> > (page fault). I didn't have much time to look into that, but what I've >> > observed is that the page fault ocurred during the search of PE/COFF >> > image base address (in PeCoffSearchImageBase). The function attempts to >> > search for the image base from "Address" through 0, so any of those >> > dereferenced addresses triggers the page fault. >> > >> > Do you know how we could fix that issue? Perhaps introducing a >> > AddressValidationLib (as Brian suggested previously) and use it within >> > PeCoffSearchImageBase()? >> > >> > I'd also like to thank Brian & Jeff for all the support! >> > >> > Thanks >> > Paulo >> > >> > Repo: https://github.com/pcacjr/edk2.git >> > Branch: stacktrace_v5 >> > >> > Cc: Rick Bramley <richard.bram...@hp.com> >> > Cc: Kimon Berlin <kimon.ber...@hp.com> >> > Cc: Diego Medaglia <diego.meag...@hp.com> >> > Cc: Andrew Fish <af...@apple.com> >> > Cc: Eric Dong <eric.d...@intel.com> >> > Cc: Laszlo Ersek <ler...@redhat.com> >> > Cc: Brian Johnson <brian.john...@hpe.com> >> > Cc: Jeff Fan <vanjeff_...@hotmail.com> >> > Cc: Jiewen Yao <jiewen....@intel.com> >> > Cc: Paulo Alcantara <pa...@hp.com> >> > Contributed-under: TianoCore Contribution Agreement 1.1 >> > Signed-off-by: Paulo Alcantara <pa...@paulo.ac> >> > --- >> > >> > v1 -> v2: >> > * Add IA32 arch support (GCC toolchain only) >> > * Replace hard-coded stack alignment value (16) with >> > CPU_STACK_ALIGNMENT. >> > * Check for proper stack and frame pointer alignments. >> > * Fix initialization of UnwoundStacksCount to 1. >> > * Move GetPdbFileName() to common code since it will be used by both >> > IA32 and X64 implementations. >> > >> > v2 -> v3: >> > * Fixed wrong assumption about "RIP < ImageBase" to start searching >> > for another PE/COFF image. That is, RIP may point to lower and >> > higher addresses for any other PE/COFF images. Both IA32 & X64. >> > (Thanks Andrew & Jiewen) >> > * Fixed typo: unwond -> unwound. Both IA32 & X64. (Thanks Brian) >> > >> > v3 -> v4: >> > * Validate all frame/stack pointer addresses before dereferencing them >> > as requested by Brian & Jiewen. >> > * Correctly print out IP addresses during the stack traces (by Jeff) >> > >> > v4 -> v5: >> > * Fixed address calculations and improved code as suggested by Jiewen. >> > * Fixed parameter validation as suggested by Brian. >> > * Tested stack stack with IA32 PAE paging mode. >> > >> > Paulo Alcantara (8): >> > UefiCpuPkg/CpuExceptionHandlerLib/X64: Add stack trace support >> > UefiCpuPkg/CpuExceptionHandlerLib: Export GetPdbFileName() >> > UefiCpuPkg/CpuExceptionHandlerLib/Ia32: Add stack trace support >> > UefiCpuPkg/CpuExceptionHandlerLib: Add helper to validate memory >> > addresses >> > UefiCpuPkg/CpuExceptionHandlerLib: Ensure valid frame/stack pointers >> > UefiCpuPkg/CpuExceptionHandlerLib: Correctly print IP addresses >> > UefiCpuPkg/CpuExceptionHandlerLib: Validate memory address ranges >> > UefiCpuPkg/CpuExceptionHandlerLib: Add early check in >> > DumpStackContents >> > >> > UefiCpuPkg/Library/CpuExceptionHandlerLib/CpuExceptionCommon.c >> > | 537 ++++++++++++++++++-- >> > UefiCpuPkg/Library/CpuExceptionHandlerLib/CpuExceptionCommon.h >> > | 59 ++- >> > UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c | >> > 483 +++++++++++++++++- >> > UefiCpuPkg/Library/CpuExceptionHandlerLib/X64/ArchExceptionHandler.c >> | >> > 426 +++++++++++++++- >> > 4 files changed, 1435 insertions(+), 70 deletions(-) >> > >> > -- >> > 2.14.3 >> > >> > _______________________________________________ >> > 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 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
