Kernel: Fix out of bounds reads on storage devices

This commit is contained in:
2026-07-13 08:06:37 +03:00
parent 02f05436fc
commit 96e5779182

View File

@@ -301,22 +301,44 @@ namespace Kernel
BAN::ErrorOr<size_t> StorageDevice::read_impl(off_t offset, BAN::ByteSpan buffer) BAN::ErrorOr<size_t> StorageDevice::read_impl(off_t offset, BAN::ByteSpan buffer)
{ {
if (offset % sector_size()) if (offset < 0 || offset % sector_size())
return BAN::Error::from_errno(EINVAL); return BAN::Error::from_errno(EINVAL);
if (buffer.size() % sector_size())
return BAN::Error::from_errno(EINVAL); const uint64_t total_blocks = total_size() / sector_size();
TRY(read_sectors(offset / sector_size(), buffer.size() / sector_size(), buffer));
return buffer.size(); const uint64_t first_block = offset / sector_size();
uint64_t block_count = buffer.size() / sector_size();
if (first_block >= total_blocks)
return 0;
if (first_block + block_count > total_blocks)
block_count = m_blocks - first_block;
if (block_count == 0)
return 0;
TRY(read_sectors(first_block, block_count, buffer));
return block_count * sector_size();
} }
BAN::ErrorOr<size_t> StorageDevice::write_impl(off_t offset, BAN::ConstByteSpan buffer) BAN::ErrorOr<size_t> StorageDevice::write_impl(off_t offset, BAN::ConstByteSpan buffer)
{ {
if (offset % sector_size()) if (offset < 0 || offset % sector_size())
return BAN::Error::from_errno(EINVAL); return BAN::Error::from_errno(EINVAL);
if (buffer.size() % sector_size())
return BAN::Error::from_errno(EINVAL); const uint64_t total_blocks = total_size() / sector_size();
TRY(write_sectors(offset / sector_size(), buffer.size() / sector_size(), buffer));
return buffer.size(); const uint64_t first_block = offset / sector_size();
uint64_t block_count = buffer.size() / sector_size();
if (first_block >= total_blocks)
return 0;
if (first_block + block_count > total_blocks)
block_count = m_blocks - first_block;
if (block_count == 0)
return 0;
TRY(write_sectors(first_block, block_count, buffer));
return block_count * sector_size();
} }
} }