From 1116e0e372eb16dd907ec571ce5d4af325c55c10 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Fri, 23 Aug 2024 18:27:39 -0400 Subject: [PATCH] nfsd: fix potential UAF in nfsd4_cb_getattr_release Once we drop the delegation reference, the fields embedded in it are no longer safe to access. Do that last. Fixes: c5967721e106 ("NFSD: handle GETATTR conflict with write delegation") Signed-off-by: Jeff Layton Signed-off-by: Chuck Lever --- fs/nfsd/nfs4state.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 19d39872be32..02d43f95146e 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -3078,9 +3078,9 @@ nfsd4_cb_getattr_release(struct nfsd4_callback *cb) struct nfs4_delegation *dp = container_of(ncf, struct nfs4_delegation, dl_cb_fattr); - nfs4_put_stid(&dp->dl_stid); clear_bit(CB_GETATTR_BUSY, &ncf->ncf_cb_flags); wake_up_bit(&ncf->ncf_cb_flags, CB_GETATTR_BUSY); + nfs4_put_stid(&dp->dl_stid); } static const struct nfsd4_callback_ops nfsd4_cb_recall_any_ops = { -- 2.25.1