From 895f54f4873198c057b5189c29aba4009d5e1031 Mon Sep 17 00:00:00 2001 From: Andrew Kaster Date: Fri, 17 Feb 2023 10:25:55 -0700 Subject: [PATCH] LibDeviceTree: Refactor dump() to return ErrorOr, and use ReadonlyBytes ReadonlyBytes is much nicer to use than a u8 const* + size_t. --- .../Libraries/LibDeviceTree/Validation.cpp | 41 ++++++++++--------- Userland/Libraries/LibDeviceTree/Validation.h | 6 +-- Userland/Utilities/fdtdump.cpp | 7 ++-- 3 files changed, 28 insertions(+), 26 deletions(-) diff --git a/Userland/Libraries/LibDeviceTree/Validation.cpp b/Userland/Libraries/LibDeviceTree/Validation.cpp index 7404231b36..a30312a3ea 100644 --- a/Userland/Libraries/LibDeviceTree/Validation.cpp +++ b/Userland/Libraries/LibDeviceTree/Validation.cpp @@ -1,5 +1,5 @@ /* - * Copyright (c) 2021, Andrew Kaster + * Copyright (c) 2021-2023, Andrew Kaster * * SPDX-License-Identifier: BSD-2-Clause */ @@ -7,11 +7,12 @@ #include #include #include +#include #include namespace DeviceTree { -bool validate_flattened_device_tree(FlattenedDeviceTreeHeader const& header, u8 const* blob_start, size_t blob_size, Verbose verbose) +bool validate_flattened_device_tree(FlattenedDeviceTreeHeader const& header, ReadonlyBytes raw_device_tree, Verbose verbose) { if (header.magic != 0xD00DFEEDU) { if (verbose == Verbose::Yes) @@ -31,27 +32,27 @@ bool validate_flattened_device_tree(FlattenedDeviceTreeHeader const& header, u8 return false; } - if (header.totalsize != blob_size) { + if (header.totalsize != raw_device_tree.size()) { if (verbose == Verbose::Yes) - warnln("FDT Header total size mismatch: {}, expected {}!", header.totalsize, blob_size); + warnln("FDT Header total size mismatch: {}, expected {}!", header.totalsize, raw_device_tree.size()); return false; } - if (header.off_dt_struct > blob_size) { + if (header.off_dt_struct > raw_device_tree.size()) { if (verbose == Verbose::Yes) - warnln("FDT Header reports larger StructureBlock offset than possible: {} but total size is {}!", header.off_dt_struct, blob_size); + warnln("FDT Header reports larger StructureBlock offset than possible: {} but total size is {}!", header.off_dt_struct, raw_device_tree.size()); return false; } - if (header.off_dt_strings > blob_size) { + if (header.off_dt_strings > raw_device_tree.size()) { if (verbose == Verbose::Yes) - warnln("FDT Header reports larger StringsBlock offset than possible: {} but total size is {}!", header.off_dt_strings, blob_size); + warnln("FDT Header reports larger StringsBlock offset than possible: {} but total size is {}!", header.off_dt_strings, raw_device_tree.size()); return false; } - if (header.off_mem_rsvmap > blob_size) { + if (header.off_mem_rsvmap > raw_device_tree.size()) { if (verbose == Verbose::Yes) - warnln("FDT Header reports larger MemoryReservationBlock offset than possible: {} but total size is {}!", header.off_mem_rsvmap, blob_size); + warnln("FDT Header reports larger MemoryReservationBlock offset than possible: {} but total size is {}!", header.off_mem_rsvmap, raw_device_tree.size()); return false; } @@ -80,7 +81,7 @@ bool validate_flattened_device_tree(FlattenedDeviceTreeHeader const& header, u8 return false; } - auto* mem_reserve_block = reinterpret_cast(&blob_start[header.off_mem_rsvmap]); + auto* mem_reserve_block = reinterpret_cast(&raw_device_tree[header.off_mem_rsvmap]); u64 next_block_offset = header.off_mem_rsvmap + sizeof(FlattenedDeviceTreeReserveEntry); while ((next_block_offset < header.off_dt_struct) && (*mem_reserve_block != FlattenedDeviceTreeReserveEntry {})) { ++mem_reserve_block; @@ -95,23 +96,23 @@ bool validate_flattened_device_tree(FlattenedDeviceTreeHeader const& header, u8 // check for overlap. Overflow not possible b/c the fields are u32 u64 structure_block_size = header.off_dt_struct + header.size_dt_struct; - if ((structure_block_size > header.off_dt_strings) || (structure_block_size > blob_size)) { + if ((structure_block_size > header.off_dt_strings) || (structure_block_size > raw_device_tree.size())) { if (verbose == Verbose::Yes) - warnln("FDT Header reports invalid StructureBlock block size: {} is too large given StringsBlock offset {} and total size {}", structure_block_size, header.off_dt_strings, blob_size); + warnln("FDT Header reports invalid StructureBlock block size: {} is too large given StringsBlock offset {} and total size {}", structure_block_size, header.off_dt_strings, raw_device_tree.size()); return false; } u64 strings_block_size = header.off_dt_strings + header.size_dt_strings; - if (strings_block_size > blob_size) { + if (strings_block_size > raw_device_tree.size()) { if (verbose == Verbose::Yes) - warnln("FDT Header reports invalid StringsBlock size: {} is too large given total size {}", strings_block_size, blob_size); + warnln("FDT Header reports invalid StringsBlock size: {} is too large given total size {}", strings_block_size, raw_device_tree.size()); return false; } return true; } -bool dump(FlattenedDeviceTreeHeader const& header, u8 const* blob_start, size_t blob_size) +ErrorOr dump(FlattenedDeviceTreeHeader const& header, ReadonlyBytes raw_device_tree) { outln("/dts-v1/;"); outln("// magic: 0x{:08x}", header.magic); @@ -125,11 +126,11 @@ bool dump(FlattenedDeviceTreeHeader const& header, u8 const* blob_start, size_t outln("// size_dt_strings: 0x{:08x}", header.size_dt_strings); outln("// size_dt_struct: 0x{:08x}", header.size_dt_struct); - if (!validate_flattened_device_tree(header, blob_start, blob_size, Verbose::Yes)) - return false; + if (!validate_flattened_device_tree(header, raw_device_tree, Verbose::Yes)) + return Error::from_errno(EINVAL); // Now that we know the device tree is valid, print out the rest of the information - auto* mem_reserve_block = reinterpret_cast(&blob_start[header.off_mem_rsvmap]); + auto const* mem_reserve_block = reinterpret_cast(&raw_device_tree[header.off_mem_rsvmap]); u64 next_block_offset = header.off_mem_rsvmap + sizeof(FlattenedDeviceTreeReserveEntry); while ((next_block_offset < header.off_dt_struct) && (*mem_reserve_block != FlattenedDeviceTreeReserveEntry {})) { outln("/memreserve/ 0x{:08x} 0x{:08x};", mem_reserve_block->address, mem_reserve_block->size); @@ -137,7 +138,7 @@ bool dump(FlattenedDeviceTreeHeader const& header, u8 const* blob_start, size_t next_block_offset += sizeof(FlattenedDeviceTreeReserveEntry); } - return true; + return {}; } } // namespace DeviceTree diff --git a/Userland/Libraries/LibDeviceTree/Validation.h b/Userland/Libraries/LibDeviceTree/Validation.h index 069ca6a818..fcd21c207e 100644 --- a/Userland/Libraries/LibDeviceTree/Validation.h +++ b/Userland/Libraries/LibDeviceTree/Validation.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2021, Andrew Kaster + * Copyright (c) 2021-2023, Andrew Kaster * * SPDX-License-Identifier: BSD-2-Clause */ @@ -15,8 +15,8 @@ enum class Verbose { Yes }; -bool validate_flattened_device_tree(FlattenedDeviceTreeHeader const& header, u8 const* blob_start, size_t blob_size, Verbose = Verbose::No); +bool validate_flattened_device_tree(FlattenedDeviceTreeHeader const& header, ReadonlyBytes raw_device_tree, Verbose = Verbose::No); -bool dump(FlattenedDeviceTreeHeader const& header, u8 const* blob_start, size_t blob_size); +ErrorOr dump(FlattenedDeviceTreeHeader const& header, ReadonlyBytes raw_device_tree); } diff --git a/Userland/Utilities/fdtdump.cpp b/Userland/Utilities/fdtdump.cpp index b6e6841c18..46ab0e3094 100644 --- a/Userland/Utilities/fdtdump.cpp +++ b/Userland/Utilities/fdtdump.cpp @@ -29,9 +29,10 @@ ErrorOr serenity_main(Main::Arguments arguments) return 1; } - auto* fdt_header = reinterpret_cast(file->data()); + auto const* fdt_header = reinterpret_cast(file->data()); + auto bytes = ReadonlyBytes { file->data(), file->size() }; - bool valid = DeviceTree::dump(*fdt_header, static_cast(file->data()), file->size()); + TRY(DeviceTree::dump(*fdt_header, bytes)); - return valid ? 0 : 1; + return 0; }