cbcvebase.
CVE-2021-46928
published 2024-02-27

CVE-2021-46928: 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…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.22%
13.2th percentile
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.

Affected

11 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.15.15-1 (bookworm)linux 5.15.15-1 (bookworm)
linuxlinux
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d01e9ce1af6116f812491d3d3873d204f10ae0b8d01e9ce1af6116f812491d3d3873d204f10ae0b8
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < e96373f0a5f484bc1e193f9951dcb3adf24bf3f7e96373f0a5f484bc1e193f9951dcb3adf24bf3f7
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 484730e5862f6b872dca13840bed40fd7c60fa26484730e5862f6b872dca13840bed40fd7c60fa26
linuxlinux_kernel< 5.10.905.10.90
linuxlinux_kernel>= 0 < 5.10.92-15.10.92-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 5.11.0 < 5.15.135.15.13

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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