In the Linux kernel, the following vulnerability has been...
Moderate severity
Unreviewed
Published
Sep 17, 2025
to the GitHub Advisory Database
•
Updated Dec 11, 2025
Description
Published by the National Vulnerability Database
Sep 17, 2025
Published to the GitHub Advisory Database
Sep 17, 2025
Last updated
Dec 11, 2025
In the Linux kernel, the following vulnerability has been resolved:
NFSv4.2: Rework scratch handling for READ_PLUS (again)
I found that the read code might send multiple requests using the same
nfs_pgio_header, but nfs4_proc_read_setup() is only called once. This is
how we ended up occasionally double-freeing the scratch buffer, but also
means we set a NULL pointer but non-zero length to the xdr scratch
buffer. This results in an oops the first time decoding needs to copy
something to scratch, which frequently happens when decoding READ_PLUS
hole segments.
I fix this by moving scratch handling into the pageio read code. I
provide a function to allocate scratch space for decoding read replies,
and free the scratch buffer when the nfs_pgio_header is freed.
References