From: Benjamin Coddington Date: Fri, 20 Nov 2015 14:56:20 +0000 (-0500) Subject: nfs4: start callback_ident at idr 1 X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=c68a027c05709330fe5b2f50c50d5fa02124b5d8;p=deliverable%2Flinux.git nfs4: start callback_ident at idr 1 If clp->cl_cb_ident is zero, then nfs_cb_idr_remove_locked() skips removing it when the nfs_client is freed. A decoding or server bug can then find and try to put that first nfs_client which would lead to a crash. Signed-off-by: Benjamin Coddington Fixes: d6870312659d ("nfs4client: convert to idr_alloc()") Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust --- diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index 223bedda64ae..10410e8b5853 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -33,7 +33,7 @@ static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion) return ret; idr_preload(GFP_KERNEL); spin_lock(&nn->nfs_client_lock); - ret = idr_alloc(&nn->cb_ident_idr, clp, 0, 0, GFP_NOWAIT); + ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT); if (ret >= 0) clp->cl_cb_ident = ret; spin_unlock(&nn->nfs_client_lock);