From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-x22f.google.com (mail-pg0-x22f.google.com [IPv6:2607:f8b0:400e:c05::22f]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 13D5B21E3EA8A for ; Mon, 4 Sep 2017 01:51:53 -0700 (PDT) Received: by mail-pg0-x22f.google.com with SMTP id 63so17047597pgc.2 for ; Mon, 04 Sep 2017 01:54:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=oOkXkhzOU0iPZ/8X6U24xMtvMVxa29Lk03GfGMXIRMA=; b=KVGrBtV5Yek2XhFyJBtEE8KSzKSzqIL1iDi1VHYQCY9VlYahntAS8YYxQ9skXUYnWZ wGfnO4DmLfmhoV4yDuZjnb4bg9Qyh4DSrcYELW7tr3eqle5WkY2YVBy0/A61UW5omDr5 /q4sonEe6mQUVNr322aftFOkxsTWKq/bgCoLnmUI5qh/wWg9Rrj0yPDQ4rVay1tZnZBT tutWvRhZHjY6CbvfyVSWD9QMaXEslWE/wSQS3+Zv0fI1DErTJdUnNg/jfY5tkuSGLI7E Ly+62w1zAWYZMq1jwyu/ciYHyckJ2Z0FgydoUEVLP39PNtcMpptSQbaSw1uyGP8NuGAF ZVdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=oOkXkhzOU0iPZ/8X6U24xMtvMVxa29Lk03GfGMXIRMA=; b=OvkUZtndY25kYzUHpCHL4DnGZkbaluxj3aY6Mv5IfDzp+yzyY3N8YCOMmASiHWqYMb jpkh08rPT0Tyd46b7C+86s8aHU6HyyY10ka4nUb/wLlh0f/mwO6sWfykzR0oQ+L6Lzqn 28sssY/X689bf5zCy8DFVfMkr5X0EyNdW5e8K2U3Wx4K7yJQJxAjrw+yfqjA2RwdBQxC 180nWSjFQSXdQ+9v3M6+v4coE8H5rT/4frwpUuEPfeDfPBZsbqFbkfl/9zz8xF3pFebG srPYq4hczkeULOFpbzRZYKB9M2bqeg/yiatwHD+xvvFjbaFEyE89NHSLCMhStkXF/dp9 qopQ== X-Gm-Message-State: AHPjjUhBIo/JndpJEY/Ux+32Ol6dqIVSfYVZIqNc21PeBsoeRSbWrFeH SR0+MNtKAVriu0mgXlY= X-Google-Smtp-Source: ADKCNb76Bnv6Tz0AyGtXCN3fYgr+e4ZCOmx6IPBJLmCFR7Jt1mUk1PiQzeuZJcyDLQ+F8dd3epkiUg== X-Received: by 10.84.211.102 with SMTP id b93mr996528pli.314.1504515280331; Mon, 04 Sep 2017 01:54:40 -0700 (PDT) Received: from [10.65.22.238] ([180.173.249.63]) by smtp.gmail.com with ESMTPSA id x4sm6219175pgt.80.2017.09.04.01.54.38 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 Sep 2017 01:54:39 -0700 (PDT) To: Laszlo Ersek , edk2-devel@lists.01.org Cc: Jordan Justen , Ard Biesheuvel References: <20170903021214.11516-1-ge.song@hxt-semitech.com> <20170903021214.11516-2-ge.song@hxt-semitech.com> <8cf35d7b-9c1c-e1a8-5896-ca709e57fef6@redhat.com> From: Ge Song Message-ID: <6e5f8cfc-029c-d022-69db-9c80f8850087@gmail.com> Date: Mon, 4 Sep 2017 16:54:35 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <8cf35d7b-9c1c-e1a8-5896-ca709e57fef6@redhat.com> Subject: Re: [PATCH v1 1/1] OvmfPkg/SecMain: Fix stack switching to permanent memory fail X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 04 Sep 2017 08:51:53 -0000 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US On 09/04/2017 04:49 AM, Laszlo Ersek wrote: > On 09/03/17 04:12, Ge Song wrote: >> In earlier PEI stage, temporary memory(Cache As Ram) is employed as stack > Please remove the "Cache As Ram" reference; it doesn't apply to OVMF. > > I suggest "temporary memory at PcdOvmfSecPeiTempRamBase" > >> and heap. We move them to the new room and do some relocation fixup when >> permanent memory becomes available. TemporaryRamMigration() >> is responsible for switching the stack. >> >> In the begining of the TemporaryRamMigration(), > I suggest rewording this as "before entering TemporaryRamMigration()" -- > when I read the above, I went looking for Ebp/Rbp manipulation within > TemporaryRamMigration(). > >> Ebp/Rbp is populated with content of Esp/Rsp and used as frame pointer, >> after the execution of SetJump/LongJump, stack migrates to new position > Please start a new sentence with "after the execution of ...". > >> while the context keeps unchanged. But when TemporaryRamMigration() exits, >> Esp/Rsp is filled with the content of Ebp/Rbp to destroy this stack frame. >> The result is, stack switches back to previous temporary momery. > s/momery/memory/ Thanks for your detailed guidance, I'll revise the things you mentioned in V2 patch. And I must express my thanks for your article "Laszlo's unkempt git guide for edk2 contributors and maintainers". It helps me a lot! > But, more importantly, what are the practical consequences of this bug? > > Does it mean that the temporary SEC/PEI stack is used until the end of > PEI, even after permanent RAM is installed, during both normal boot and > S3 resume? Yes, I think that's exactly true. > If that's the case, I wonder how it was caught. Once I was tracing a variable and found the abnormal value in SP. > If it was caught during S3 resume, then the only symptom could have been > stack overflow. Because during normal boot, both temporary and permanent > PEI RAM are reserved, so even if we stay on the temporary stack during > S3, if we don't overflow it, we cannot corrupt data: > >> /** >> Publish system RAM and reserve memory regions >> >> **/ >> VOID >> InitializeRamRegions ( >> VOID >> ) >> { >> if (!mXen) { >> QemuInitializeRam (); >> } else { >> XenPublishRamRegions (); >> } >> >> if (mS3Supported && mBootMode != BOOT_ON_S3_RESUME) { >> // >> // This is the memory range that will be used for PEI on S3 resume >> // >> BuildMemoryAllocationHob ( >> mS3AcpiReservedMemoryBase, >> mS3AcpiReservedMemorySize, >> EfiACPIMemoryNVS >> ); >> >> // >> // Cover the initial RAM area used as stack and temporary PEI heap. >> // >> // This is reserved as ACPI NVS so it can be used on S3 resume. >> // >> BuildMemoryAllocationHob ( >> PcdGet32 (PcdOvmfSecPeiTempRamBase), >> PcdGet32 (PcdOvmfSecPeiTempRamSize), >> EfiACPIMemoryNVS >> ); > With stack overflow during S3 resume, we may have corrupted OS data > residing very low. Yes, I think this is the real problem. In current implementation, stack located in temporary memory will not be exhausted during the whole PEI phase so there won't be an system crash during S3 resume caused by this. The size of stack in temporary memory is 32K, when in permanent memory it is 128K. This approximately simulate the scene in real machine. Logically the stack should be switched to permanent memory when the latter becomes available. Since hardware protection mechanism for stack is disabled, currently using larger stack can reduced the possibility of stack overflow, thus, the possibility of crash during S3 resume Check the GDT set up by reset vector module: GDT_BASE: ; null descriptor NULL_SEL equ $-GDT_BASE DW 0 ; limit 15:0 DW 0 ; base 15:0 DB 0 ; base 23:16 DB 0 ; sys flag, dpl, type DB 0 ; limit 19:16, flags DB 0 ; base 31:24 ; linear data segment descriptor LINEAR_SEL equ $-GDT_BASE DW 0xffff ; limit 15:0 DW 0 ; base 15:0 DB 0 ; base 23:16 DB PRESENT_FLAG(1)|DPL(0)|SYSTEM_FLAG(1)|DESC_TYPE(DATA32_TYPE) DB GRANULARITY_FLAG(1)|DEFAULT_SIZE32(1)|CODE64_FLAG(0)|UPPER_LIMIT(0xf) DB 0 ; base 31:24 ; linear code segment descriptor LINEAR_CODE_SEL equ $-GDT_BASE DW 0xffff ; limit 15:0 DW 0 ; base 15:0 DB 0 ; base 23:16 DB PRESENT_FLAG(1)|DPL(0)|SYSTEM_FLAG(1)|DESC_TYPE(CODE32_TYPE) DB GRANULARITY_FLAG(1)|DEFAULT_SIZE32(1)|CODE64_FLAG(0)|UPPER_LIMIT(0xf) DB 0 ; base 31:24 %ifdef ARCH_X64 ; linear code (64-bit) segment descriptor LINEAR_CODE64_SEL equ $-GDT_BASE DW 0xffff ; limit 15:0 DW 0 ; base 15:0 DB 0 ; base 23:16 DB PRESENT_FLAG(1)|DPL(0)|SYSTEM_FLAG(1)|DESC_TYPE(CODE64_TYPE) DB GRANULARITY_FLAG(1)|DEFAULT_SIZE32(0)|CODE64_FLAG(1)|UPPER_LIMIT(0xf) DB 0 ; base 31:24 %endif GDT_END: SS is set to use LINEAR_SEL descriptor, actually stack protection provided by hardware is disabled BTW, is it better to utilize the hardware mechanism to set up stack overflow protection in both stage(pre-memory and post-memory)? > > However, if the bug was caught during normal boot, then I don't know > what the symptom may have been. The permanent PEI RAM for normal boot is > pretty close to the top of low RAM (and the default RAM size for QEMU is > 128MB). The temporary stack is very low however ("Temp Stack : > BaseAddress=0x814000 Length=0x4000"). So even if we overflow the > temporary stack (i.e. go below the address 0x814000) during normal boot, > I don't think anything allocated from the permanent PEI RAM could be > corrupted by that. I strongly agree with you. Normal boot shouldn't be affected even stack overflows. > I'll do some testing in the next few days. > > The analysis and the patch look great (and impressive!) to me. I'd like > the commit message to be cleaned up a bit -- please see my notes above, > and please describe: > > - practical consequences of the bug, > > - how the bug was caught. > > I have one more (superficial) comment below: > >> More detailed information: >>> TemporaryRamMigration (PeiServices=0x817790, >>> TemporaryMemoryBase=8454144, PermanentMemoryBase=469016576, >>> CopySize=32768) >>> at /home/bird/src/edk2/OvmfPkg/Sec/SecMain.c:938 >>> 938 LongJump (&JumpBuffer, (UINTN)-1); >>> (gdb) info registers >>> rax 0x1bf4d3b0 469029808 >>> rbx 0x810248 8454728 >>> rcx 0x8173e8 8483816 >>> rdx 0x8173b0 8483760 >>> rsi 0x1bf4a000 469016576 >>> rdi 0x8000 32768 >>> rbp 0x817520 0x817520 >>> rsp 0x8173b0 0x8173b0 >>> r8 0x0 0 >>> ... >>> rip 0xfffcd409 0xfffcd409 >>> eflags 0x2 [ ] >>> cs 0x18 24 >>> ss 0x8 8 >>> ... >> After execution of LongJump: >>> 943 return EFI_SUCCESS; >>> (gdb) info registers >>> rax 0x0 0 >>> rbx 0x810248 8454728 >>> rcx 0x0 0 >>> rdx 0xffffffffffffffff -1 >>> rsi 0x1bf4a000 469016576 >>> rdi 0x8000 32768 >>> rbp 0x817520 0x817520 >>> rsp 0x1bf4d3b0 0x1bf4d3b0 >>> r8 0x0 0 >>> ... >>> rip 0xfffcd42a 0xfffcd42a >>> eflags 0x86 [ PF SF ] >>> cs 0x18 24 >>> ss 0x8 8 >>> ... >> We can find rsp has changed to new permanent memory >> >> When leaving TemporaryRamMigration(), the stack swithes back to previous >> temporary memory: >>> (gdb) finish >>> Run till exit from #0 TemporaryRamMigration (PeiServices=0x817790, >>> TemporaryMemoryBase=8454144, PermanentMemoryBase=469016576, >>> CopySize=32768) >>> at /home/bird/src/edk2/OvmfPkg/Sec/SecMain.c:943 >>> PeiCheckAndSwitchStack (SecCoreData=0x1bf4df78, Private=0x1bf4d788) at >>> /home/bird/src/edk2/MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c:806 >>> 806 PeiCore (SecCoreData, NULL, Private); >>> Value returned is $1 = 0 >>> (gdb) info registers >>> rax 0x0 0 >>> rbx 0x810248 8454728 >>> rcx 0x0 0 >>> rdx 0xffffffffffffffff -1 >>> rsi 0x1bf4a000 469016576 >>> rdi 0x8000 32768 >>> rbp 0x817630 0x817630 >>> rsp 0x817530 0x817530 >>> r8 0x0 0 >>> ... >>> rip 0x828135 0x828135 >>> eflags 0x86 [ PF SF ] >>> cs 0x18 24 >>> ss 0x8 8 >>> ... >>> (gdb) disassemble /r >>> Dump of assembler code for function TemporaryRamMigration: >>> 0x00000000fffcd29c <+0>: 55 push %rbp >>> 0x00000000fffcd29d <+1>: 48 89 e5 mov %rsp,%rbp >>> 0x00000000fffcd2a0 <+4>: 48 81 ec 70 01 00 00 sub >>> $0x170,%rsp >>> ... >>> ... >>> 0x00000000fffcd425 <+393>: e8 80 10 00 00 callq 0xfffce4aa >>> >>> => 0x00000000fffcd42a <+398>: b8 00 00 00 00 mov $0x0,%eax >>> 0x00000000fffcd42f <+403>: c9 leaveq >>> 0x00000000fffcd430 <+404>: c3 retq >>> End of assembler dump. >> See the description of leave(opcode: c9), from >> Intel® 64 and IA-32 Architectures Software Developers Manual, Volume 2A > I prefer keeping commit messages ASCII-clean. > > Thanks > Laszlo > >> "Releases the stack frame set up by an earlier ENTER instruction. The >> LEAVE instruction copies the frame pointer (in the EBP register) into >> the stack pointer register (ESP), which releases the stack space >> allocated to the stack frame. The old frame pointer (the frame pointer >> for the calling procedure that was saved by the ENTER instruction) is >> then popped from the stack into the EBP register, restoring the calling >> procedures stack frame." >> >> To solve this, update Ebp/Rbp too when Esp/Rsp is updated >> >> Cc: Jordan Justen >> Cc: Laszlo Ersek >> Cc: Ard Biesheuvel >> Contributed-under: TianoCore Contribution Agreement 1.1 >> Signed-off-by: Ge Song >> --- >> OvmfPkg/Sec/SecMain.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/OvmfPkg/Sec/SecMain.c b/OvmfPkg/Sec/SecMain.c >> index e1993ec347b5..f7fec3d8c03b 100644 >> --- a/OvmfPkg/Sec/SecMain.c >> +++ b/OvmfPkg/Sec/SecMain.c >> @@ -931,9 +931,11 @@ TemporaryRamMigration ( >> if (SetJump (&JumpBuffer) == 0) { >> #if defined (MDE_CPU_IA32) >> JumpBuffer.Esp = JumpBuffer.Esp + DebugAgentContext.StackMigrateOffset; >> + JumpBuffer.Ebp = JumpBuffer.Ebp + DebugAgentContext.StackMigrateOffset; >> #endif >> #if defined (MDE_CPU_X64) >> JumpBuffer.Rsp = JumpBuffer.Rsp + DebugAgentContext.StackMigrateOffset; >> + JumpBuffer.Rbp = JumpBuffer.Rbp + DebugAgentContext.StackMigrateOffset; >> #endif >> LongJump (&JumpBuffer, (UINTN)-1); >> } >> On 09/04/2017 04:49 AM, Laszlo Ersek wrote: > On 09/03/17 04:12, Ge Song wrote: >> In earlier PEI stage, temporary memory(Cache As Ram) is employed as stack > Please remove the "Cache As Ram" reference; it doesn't apply to OVMF. > > I suggest "temporary memory at PcdOvmfSecPeiTempRamBase" > >> and heap. We move them to the new room and do some relocation fixup when >> permanent memory becomes available. TemporaryRamMigration() >> is responsible for switching the stack. >> >> In the begining of the TemporaryRamMigration(), > I suggest rewording this as "before entering TemporaryRamMigration()" -- > when I read the above, I went looking for Ebp/Rbp manipulation within > TemporaryRamMigration(). > >> Ebp/Rbp is populated with content of Esp/Rsp and used as frame pointer, >> after the execution of SetJump/LongJump, stack migrates to new position > Please start a new sentence with "after the execution of ...". > >> while the context keeps unchanged. But when TemporaryRamMigration() exits, >> Esp/Rsp is filled with the content of Ebp/Rbp to destroy this stack frame. >> The result is, stack switches back to previous temporary momery. > s/momery/memory/ > > > But, more importantly, what are the practical consequences of this bug? > > Does it mean that the temporary SEC/PEI stack is used until the end of > PEI, even after permanent RAM is installed, during both normal boot and > S3 resume? > > If that's the case, I wonder how it was caught. > > If it was caught during S3 resume, then the only symptom could have been > stack overflow. Because during normal boot, both temporary and permanent > PEI RAM are reserved, so even if we stay on the temporary stack during > S3, if we don't overflow it, we cannot corrupt data: > >> /** >> Publish system RAM and reserve memory regions >> >> **/ >> VOID >> InitializeRamRegions ( >> VOID >> ) >> { >> if (!mXen) { >> QemuInitializeRam (); >> } else { >> XenPublishRamRegions (); >> } >> >> if (mS3Supported && mBootMode != BOOT_ON_S3_RESUME) { >> // >> // This is the memory range that will be used for PEI on S3 resume >> // >> BuildMemoryAllocationHob ( >> mS3AcpiReservedMemoryBase, >> mS3AcpiReservedMemorySize, >> EfiACPIMemoryNVS >> ); >> >> // >> // Cover the initial RAM area used as stack and temporary PEI heap. >> // >> // This is reserved as ACPI NVS so it can be used on S3 resume. >> // >> BuildMemoryAllocationHob ( >> PcdGet32 (PcdOvmfSecPeiTempRamBase), >> PcdGet32 (PcdOvmfSecPeiTempRamSize), >> EfiACPIMemoryNVS >> ); > With stack overflow during S3 resume, we may have corrupted OS data > residing very low. > > However, if the bug was caught during normal boot, then I don't know > what the symptom may have been. The permanent PEI RAM for normal boot is > pretty close to the top of low RAM (and the default RAM size for QEMU is > 128MB). The temporary stack is very low however ("Temp Stack : > BaseAddress=0x814000 Length=0x4000"). So even if we overflow the > temporary stack (i.e. go below the address 0x814000) during normal boot, > I don't think anything allocated from the permanent PEI RAM could be > corrupted by that. > > I'll do some testing in the next few days. > > The analysis and the patch look great (and impressive!) to me. I'd like > the commit message to be cleaned up a bit -- please see my notes above, > and please describe: > > - practical consequences of the bug, > > - how the bug was caught. > > I have one more (superficial) comment below: > >> More detailed information: >>> TemporaryRamMigration (PeiServices=0x817790, >>> TemporaryMemoryBase=8454144, PermanentMemoryBase=469016576, >>> CopySize=32768) >>> at /home/bird/src/edk2/OvmfPkg/Sec/SecMain.c:938 >>> 938 LongJump (&JumpBuffer, (UINTN)-1); >>> (gdb) info registers >>> rax 0x1bf4d3b0 469029808 >>> rbx 0x810248 8454728 >>> rcx 0x8173e8 8483816 >>> rdx 0x8173b0 8483760 >>> rsi 0x1bf4a000 469016576 >>> rdi 0x8000 32768 >>> rbp 0x817520 0x817520 >>> rsp 0x8173b0 0x8173b0 >>> r8 0x0 0 >>> ... >>> rip 0xfffcd409 0xfffcd409 >>> eflags 0x2 [ ] >>> cs 0x18 24 >>> ss 0x8 8 >>> ... >> After execution of LongJump: >>> 943 return EFI_SUCCESS; >>> (gdb) info registers >>> rax 0x0 0 >>> rbx 0x810248 8454728 >>> rcx 0x0 0 >>> rdx 0xffffffffffffffff -1 >>> rsi 0x1bf4a000 469016576 >>> rdi 0x8000 32768 >>> rbp 0x817520 0x817520 >>> rsp 0x1bf4d3b0 0x1bf4d3b0 >>> r8 0x0 0 >>> ... >>> rip 0xfffcd42a 0xfffcd42a >>> eflags 0x86 [ PF SF ] >>> cs 0x18 24 >>> ss 0x8 8 >>> ... >> We can find rsp has changed to new permanent memory >> >> When leaving TemporaryRamMigration(), the stack swithes back to previous >> temporary memory: >>> (gdb) finish >>> Run till exit from #0 TemporaryRamMigration (PeiServices=0x817790, >>> TemporaryMemoryBase=8454144, PermanentMemoryBase=469016576, >>> CopySize=32768) >>> at /home/bird/src/edk2/OvmfPkg/Sec/SecMain.c:943 >>> PeiCheckAndSwitchStack (SecCoreData=0x1bf4df78, Private=0x1bf4d788) at >>> /home/bird/src/edk2/MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c:806 >>> 806 PeiCore (SecCoreData, NULL, Private); >>> Value returned is $1 = 0 >>> (gdb) info registers >>> rax 0x0 0 >>> rbx 0x810248 8454728 >>> rcx 0x0 0 >>> rdx 0xffffffffffffffff -1 >>> rsi 0x1bf4a000 469016576 >>> rdi 0x8000 32768 >>> rbp 0x817630 0x817630 >>> rsp 0x817530 0x817530 >>> r8 0x0 0 >>> ... >>> rip 0x828135 0x828135 >>> eflags 0x86 [ PF SF ] >>> cs 0x18 24 >>> ss 0x8 8 >>> ... >>> (gdb) disassemble /r >>> Dump of assembler code for function TemporaryRamMigration: >>> 0x00000000fffcd29c <+0>: 55 push %rbp >>> 0x00000000fffcd29d <+1>: 48 89 e5 mov %rsp,%rbp >>> 0x00000000fffcd2a0 <+4>: 48 81 ec 70 01 00 00 sub >>> $0x170,%rsp >>> ... >>> ... >>> 0x00000000fffcd425 <+393>: e8 80 10 00 00 callq 0xfffce4aa >>> >>> => 0x00000000fffcd42a <+398>: b8 00 00 00 00 mov $0x0,%eax >>> 0x00000000fffcd42f <+403>: c9 leaveq >>> 0x00000000fffcd430 <+404>: c3 retq >>> End of assembler dump. >> See the description of leave(opcode: c9), from >> Intel® 64 and IA-32 Architectures Software Developers Manual, Volume 2A > I prefer keeping commit messages ASCII-clean. > > Thanks > Laszlo > >> "Releases the stack frame set up by an earlier ENTER instruction. The >> LEAVE instruction copies the frame pointer (in the EBP register) into >> the stack pointer register (ESP), which releases the stack space >> allocated to the stack frame. The old frame pointer (the frame pointer >> for the calling procedure that was saved by the ENTER instruction) is >> then popped from the stack into the EBP register, restoring the calling >> procedures stack frame." >> >> To solve this, update Ebp/Rbp too when Esp/Rsp is updated >> >> Cc: Jordan Justen >> Cc: Laszlo Ersek >> Cc: Ard Biesheuvel >> Contributed-under: TianoCore Contribution Agreement 1.1 >> Signed-off-by: Ge Song >> --- >> OvmfPkg/Sec/SecMain.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/OvmfPkg/Sec/SecMain.c b/OvmfPkg/Sec/SecMain.c >> index e1993ec347b5..f7fec3d8c03b 100644 >> --- a/OvmfPkg/Sec/SecMain.c >> +++ b/OvmfPkg/Sec/SecMain.c >> @@ -931,9 +931,11 @@ TemporaryRamMigration ( >> if (SetJump (&JumpBuffer) == 0) { >> #if defined (MDE_CPU_IA32) >> JumpBuffer.Esp = JumpBuffer.Esp + DebugAgentContext.StackMigrateOffset; >> + JumpBuffer.Ebp = JumpBuffer.Ebp + DebugAgentContext.StackMigrateOffset; >> #endif >> #if defined (MDE_CPU_X64) >> JumpBuffer.Rsp = JumpBuffer.Rsp + DebugAgentContext.StackMigrateOffset; >> + JumpBuffer.Rbp = JumpBuffer.Rbp + DebugAgentContext.StackMigrateOffset; >> #endif >> LongJump (&JumpBuffer, (UINTN)-1); >> } >>