This is a note to let you know that I've just added the patch titled
nfsd: memory corruption in nfsd4_lock()
to the 5.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfsd-memory-corruption-in-nfsd4_lock.patch
and it can be found in the queue-5.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 2b36581ddd6f5ed73a88f5a48ff22d927b61fc9b
Author: Vasily Averin <vvs@xxxxxxxxxxxxx>
Date: Fri Mar 27 07:50:40 2020 +0300
nfsd: memory corruption in nfsd4_lock()
commit e1e8399eee72e9d5246d4d1bcacd793debe34dd3 upstream.
New struct nfsd4_blocked_lock allocated in find_or_allocate_block()
does not initialized nbl_list and nbl_lru.
If conflock allocation fails rollback can call list_del_init()
access uninitialized fields and corrupt memory.
v2: just initialize nbl_list and nbl_lru right after nbl allocation.
Fixes: 76d348fadff5 ("nfsd: have nfsd4_lock use blocking locks for v4.1+ lock")
Signed-off-by: Vasily Averin <vvs@xxxxxxxxxxxxx>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 65cfe9ab47be0..de9fbe7ed06ce 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -267,6 +267,8 @@ find_or_allocate_block(struct nfs4_lockowner *lo, struct knfsd_fh *fh,
if (!nbl) {
nbl= kmalloc(sizeof(*nbl), GFP_KERNEL);
if (nbl) {
+ INIT_LIST_HEAD(&nbl->nbl_list);
+ INIT_LIST_HEAD(&nbl->nbl_lru);
fh_copy_shallow(&nbl->nbl_fh, fh);
locks_init_lock(&nbl->nbl_lock);
nfsd4_init_cb(&nbl->nbl_cb, lo->lo_owner.so_client,
