Description
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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
886959f425b6a936a30b82a297ae3aecb3b8230f to < adac9f0ddd2b291c7ce41f549fdb27a13616cff5affectedfbd2a05f29a95d5b42b294bf47e55a711424965b to < a2f4cb206bd94b3f4a7bb05fcdce9525283b5681affectedfbd2a05f29a95d5b42b294bf47e55a711424965b to < ae5d5672f1db711e91db6f52df5cb16ecd8f5692affectedfbd2a05f29a95d5b42b294bf47e55a711424965b to < 303a78052091c81e9003915c521fdca1c7e117afaffected
Linux Linux
Default version status: affected
6.4affected0 to < 6.4unaffected6.4.16 to ≤ 6.4.*unaffected6.5.3 to ≤ 6.5.*unaffected6.6 to ≤ *unaffected