mirror of
https://github.com/RGBCube/serenity
synced 2025-07-26 01:17:34 +00:00
Kernel: Panic if we're about to switch to a user thread with IOPL!=0
This is a crude protection against IOPL elevation attacks. If for any reason we find ourselves about to switch to a user mode thread with IOPL != 0, we'll now simply panic the kernel. If this happens, it basically means that something tricked the kernel into incorrectly modifying the IOPL of a thread, so it's no longer safe to trust the kernel anyway.
This commit is contained in:
parent
488a613858
commit
c25cf5fb56
2 changed files with 14 additions and 0 deletions
|
@ -44,6 +44,12 @@ class PageDirectory;
|
|||
class PageTableEntry;
|
||||
|
||||
static constexpr u32 safe_eflags_mask = 0xdff;
|
||||
static constexpr u32 iopl_mask = 3u << 12;
|
||||
|
||||
inline u32 get_iopl_from_eflags(u32 eflags)
|
||||
{
|
||||
return (eflags & iopl_mask) >> 12;
|
||||
}
|
||||
|
||||
struct [[gnu::packed]] DescriptorTablePointer
|
||||
{
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue