| Message ID | 1473776268-18207-1-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | Accepted |
| Commit | 94a3845be698ddeed9d126363c755bd3bb13dd17 |
| Headers | show |
On 09/13/16 16:17, Ard Biesheuvel wrote: > When parsing the device tree to find the memory node, we are still running > with the MMU off, which means unaligned memory accesses are not allowed. > Since the FDT only mandates 32-bit alignment, 64-bit quantities are not > guaranteed to appear naturally aligned, and so should be accessed using > 32-bit accesses instead. > > Reported-by: Julien Grall <julien.grall@arm.com> > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> > --- > ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c | 14 ++++++-------- > ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c | 14 ++++++-------- > 2 files changed, 12 insertions(+), 16 deletions(-) > > diff --git a/ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c b/ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c > index 46a5fe6409f6..afdc81a8839d 100644 > --- a/ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c > +++ b/ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c > @@ -65,17 +65,15 @@ FindMemnode ( > return FALSE; > } > > - if (AddressCells == 1) { > - *SystemMemoryBase = fdt32_to_cpu (*Prop); > - } else { > - *SystemMemoryBase = fdt64_to_cpu (*(UINT64 *)Prop); > + *SystemMemoryBase = fdt32_to_cpu (Prop[0]); > + if (AddressCells > 1) { > + *SystemMemoryBase = (*SystemMemoryBase << 32) | fdt32_to_cpu (Prop[1]); > } > Prop += AddressCells; > > - if (SizeCells == 1) { > - *SystemMemorySize = fdt32_to_cpu (*Prop); > - } else { > - *SystemMemorySize = fdt64_to_cpu (*(UINT64 *)Prop); > + *SystemMemorySize = fdt32_to_cpu (Prop[0]); > + if (SizeCells > 1) { > + *SystemMemorySize = (*SystemMemorySize << 32) | fdt32_to_cpu (Prop[1]); > } > > return TRUE; > diff --git a/ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c b/ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c > index 992932ee9754..38fd5d3ed00c 100644 > --- a/ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c > +++ b/ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c > @@ -65,17 +65,15 @@ FindMemnode ( > return FALSE; > } > > - if (AddressCells == 1) { > - *SystemMemoryBase = fdt32_to_cpu (*Prop); > - } else { > - *SystemMemoryBase = fdt64_to_cpu (*(UINT64 *)Prop); > + *SystemMemoryBase = fdt32_to_cpu (Prop[0]); > + if (AddressCells > 1) { > + *SystemMemoryBase = (*SystemMemoryBase << 32) | fdt32_to_cpu (Prop[1]); > } > Prop += AddressCells; > > - if (SizeCells == 1) { > - *SystemMemorySize = fdt32_to_cpu (*Prop); > - } else { > - *SystemMemorySize = fdt64_to_cpu (*(UINT64 *)Prop); > + *SystemMemorySize = fdt32_to_cpu (Prop[0]); > + if (SizeCells > 1) { > + *SystemMemorySize = (*SystemMemorySize << 32) | fdt32_to_cpu (Prop[1]); > } > > return TRUE; > Reviewed-by: Laszlo Ersek <lersek@redhat.com> _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
diff --git a/ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c b/ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c index 46a5fe6409f6..afdc81a8839d 100644 --- a/ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c +++ b/ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c @@ -65,17 +65,15 @@ FindMemnode ( return FALSE; } - if (AddressCells == 1) { - *SystemMemoryBase = fdt32_to_cpu (*Prop); - } else { - *SystemMemoryBase = fdt64_to_cpu (*(UINT64 *)Prop); + *SystemMemoryBase = fdt32_to_cpu (Prop[0]); + if (AddressCells > 1) { + *SystemMemoryBase = (*SystemMemoryBase << 32) | fdt32_to_cpu (Prop[1]); } Prop += AddressCells; - if (SizeCells == 1) { - *SystemMemorySize = fdt32_to_cpu (*Prop); - } else { - *SystemMemorySize = fdt64_to_cpu (*(UINT64 *)Prop); + *SystemMemorySize = fdt32_to_cpu (Prop[0]); + if (SizeCells > 1) { + *SystemMemorySize = (*SystemMemorySize << 32) | fdt32_to_cpu (Prop[1]); } return TRUE; diff --git a/ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c b/ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c index 992932ee9754..38fd5d3ed00c 100644 --- a/ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c +++ b/ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c @@ -65,17 +65,15 @@ FindMemnode ( return FALSE; } - if (AddressCells == 1) { - *SystemMemoryBase = fdt32_to_cpu (*Prop); - } else { - *SystemMemoryBase = fdt64_to_cpu (*(UINT64 *)Prop); + *SystemMemoryBase = fdt32_to_cpu (Prop[0]); + if (AddressCells > 1) { + *SystemMemoryBase = (*SystemMemoryBase << 32) | fdt32_to_cpu (Prop[1]); } Prop += AddressCells; - if (SizeCells == 1) { - *SystemMemorySize = fdt32_to_cpu (*Prop); - } else { - *SystemMemorySize = fdt64_to_cpu (*(UINT64 *)Prop); + *SystemMemorySize = fdt32_to_cpu (Prop[0]); + if (SizeCells > 1) { + *SystemMemorySize = (*SystemMemorySize << 32) | fdt32_to_cpu (Prop[1]); } return TRUE;
When parsing the device tree to find the memory node, we are still running with the MMU off, which means unaligned memory accesses are not allowed. Since the FDT only mandates 32-bit alignment, 64-bit quantities are not guaranteed to appear naturally aligned, and so should be accessed using 32-bit accesses instead. Reported-by: Julien Grall <julien.grall@arm.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/FdtParser.c | 14 ++++++-------- ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/FdtParser.c | 14 ++++++-------- 2 files changed, 12 insertions(+), 16 deletions(-) -- 2.7.4 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel