Operating system pagesize compatibility workarounds
AssigneeArm Limited
InventorsDániel Kristóf Kiss, Branislav Rankov, Ian James Rickards
Life of this patent
Estimating the term…
Abstract
A method is presented that includes detecting, by a loader, overlapping permissions for a page while loading a binary file. When writable data overlaps with read-only code in a page, the loader copies the code part of the page with the overlapping permissions to a new page. The original page is set non-executable. The new page can be set executable but read-only. When execution reaches the now non-executable original page, a segmentation fault may be raised. A signal handler installed by the loader detects that the fault is coming from the original page and redirects execution to the new page with the copied code part.
Claims20
A method comprising:
- detecting, by a loader, overlapping permissions of segments for an original page while loading a binary file, wherein the segments for the original page comprise a writable data segment and a read-only code segment;
- copying the read-only code segment to a new page;
- and
- setting the original page as non-executable.
A non-transitory computer-readable storage medium having instructions stored thereon that when executed by a processor direct a computing system to:
- detect, by a loader, overlapping permissions of segments for an original page while loading a binary file, wherein the segments for the original page comprise a writable data segment and a read-only code segment;
- copy the read-only code segment to a new page;
- and
- set the original page as non-executable.
Dependencies are inferred from the claim text.