From: Vasily Averin vvs@virtuozzo.com
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@virtuozzo.com Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/nfsd/nfs4state.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -252,6 +252,8 @@ find_or_allocate_block(struct nfs4_locko 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,