cve-2021-46928
Vulnerability from cvelistv5
Published
2024-02-27 09:43
Modified
2024-12-19 07:31
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: parisc: Clear stale IIR value on instruction access rights trap When a trap 7 (Instruction access rights) occurs, this means the CPU couldn't execute an instruction due to missing execute permissions on the memory region. In this case it seems the CPU didn't even fetched the instruction from memory and thus did not store it in the cr19 (IIR) register before calling the trap handler. So, the trap handler will find some random old stale value in cr19. This patch simply overwrites the stale IIR value with a constant magic "bad food" value (0xbaadf00d), in the hope people don't start to try to understand the various random IIR values in trap 7 dumps.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/484730e5862f6b872dca13840bed40fd7c60fa26Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d01e9ce1af6116f812491d3d3873d204f10ae0b8Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e96373f0a5f484bc1e193f9951dcb3adf24bf3f7Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/484730e5862f6b872dca13840bed40fd7c60fa26Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/d01e9ce1af6116f812491d3d3873d204f10ae0b8Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/e96373f0a5f484bc1e193f9951dcb3adf24bf3f7Patch
Impacted products
Vendor Product Version
Linux Linux
Show details on NVD website

To clipboard 

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