diff options
author | J. Bruce Fields <bfields@redhat.com> | 2021-11-29 15:08:00 -0500 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-12-22 09:29:35 +0100 |
commit | e0759696de6851d7536efddfdd2dfed4c4df1f09 (patch) | |
tree | af5420cbab0ac88c97116f9d16ae5f7381e13854 /arch/arm64/boot/dts/rockchip | |
parent | 7243aa71509a83409bf5a086ea24f029afb7bb69 (diff) |
nfsd: fix use-after-free due to delegation race
commit 548ec0805c399c65ed66c6641be467f717833ab5 upstream.
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.
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[Salvatore Bonaccorso: Backport for context changes to versions which do
not have 20b7d86f29d3 ("nfsd: use boottime for lease expiry calculation")]
Signed-off-by: Salvatore Bonaccorso <carnil@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm64/boot/dts/rockchip')
0 files changed, 0 insertions, 0 deletions