Description · from the CVE record
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix use-after-free due to delegation race
A delegation break could arrive as soon as we've called vfs_setlease. A
delegation break runs a callback which immediately (in
nfsd4_cb_recall_prepare) adds the delegation to del_recall_lru. If we
then exit nfs4_set_delegation without hashing the delegation, it will be
freed as soon as the callback is done with it, without ever being
removed from del_recall_lru.
Symptoms show up later as use-after-free or list corruption warnings,
usually in the laundromat thread.
I suspect aba2072f4523 "nfsd: grant read delegations to clients holding
writes" made this bug easier to hit, but I looked as far back as v3.0
and it looks to me it already had the same problem. So I'm not sure
where the bug was introduced; it may have been there from the beginning.
Affected
ProductAffectedFixed inSource
Linuxdff1399f8addf7129c49bb2227469da79cc30b47 – < 04a8d07f3d58308b92630045560799a3faa3ebce04a8d07f3d58308b92630045560799a3faa3ebceCNA
Linuxdff1399f8addf7129c49bb2227469da79cc30b47 – < 348714018139c39533c55661a0c7c990671396b4348714018139c39533c55661a0c7c990671396b4CNA
Linuxdff1399f8addf7129c49bb2227469da79cc30b47 – < 33645d3e22720cac1e4548f8fef57bf0649536ee33645d3e22720cac1e4548f8fef57bf0649536eeCNA
Linuxdff1399f8addf7129c49bb2227469da79cc30b47 – < 2becaa990b93cbd2928292c0b669d3abb6cf06d42becaa990b93cbd2928292c0b669d3abb6cf06d4CNA
Linuxdff1399f8addf7129c49bb2227469da79cc30b47 – < e0759696de6851d7536efddfdd2dfed4c4df1f09e0759696de6851d7536efddfdd2dfed4c4df1f09CNA
Linuxdff1399f8addf7129c49bb2227469da79cc30b47 – < eeb0711801f5e19ef654371b627682aed3b11373eeb0711801f5e19ef654371b627682aed3b11373CNA
Linuxdff1399f8addf7129c49bb2227469da79cc30b47 – < 148c816f10fd11df27ca6a9b3238cdd42fa72cd3148c816f10fd11df27ca6a9b3238cdd42fa72cd3CNA
Linuxdff1399f8addf7129c49bb2227469da79cc30b47 – < 548ec0805c399c65ed66c6641be467f717833ab5548ec0805c399c65ed66c6641be467f717833ab5CNA
Linux3.17–CNA
by Kastro