RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-24 18:47:41 +00:00
Code Issues Activity Actions

Kernel: Make validate_read_from_kernel() return early for nullptr checks.

Browse source 
Null pointers are always invalid, so don't bother going through all the
various checks for them.
This commit is contained in:
Andreas Kling 2019-04-15 23:48:31 +02:00
parent 9eab8734fe
commit ae0dc22716
1 changed files with 2 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

2
Kernel/Process.cpp
View file

@ -1371,6 +1371,8 @@ static KernelMemoryCheckResult check_kernel_memory_access(LinearAddress laddr, b
bool Process::validate_read_from_kernel(LinearAddress laddr) const bool Process::validate_read_from_kernel(LinearAddress laddr) const
{ {
if (laddr.is_null())
return false;
// We check extra carefully here since the first 4MB of the address space is identity-mapped. // We check extra carefully here since the first 4MB of the address space is identity-mapped.
// This code allows access outside of the known used address ranges to get caught. // This code allows access outside of the known used address ranges to get caught.
auto kmc_result = check_kernel_memory_access(laddr, false); auto kmc_result = check_kernel_memory_access(laddr, false);