From 38e0b7f55906a4f8208b0b07f2df22743810240a Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Thu, 27 Oct 2022 16:45:14 -0400 Subject: [PATCH] fs: dlm: use packet in dlm_mhandle [ Upstream commit 20e8ad8a46be565e7fff262b0ca1988faccdda3d ] To allow more than just dereferencing the inner header we directly point to the inner dlm packet which allows us to dereference the header, rcom or message structure. Signed-off-by: Alexander Aring Signed-off-by: David Teigland Stable-dep-of: caf2799e0b84 ("fs: dlm: fix use after free in midcomms commit") Signed-off-by: Sasha Levin --- fs/dlm/midcomms.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/dlm/midcomms.c b/fs/dlm/midcomms.c index 095f2005fb621..4a8721ab9f149 100644 --- a/fs/dlm/midcomms.c +++ b/fs/dlm/midcomms.c @@ -194,7 +194,7 @@ struct midcomms_node { }; struct dlm_mhandle { - const struct dlm_header *inner_hd; + const union dlm_packet *inner_p; struct midcomms_node *node; struct dlm_opts *opts; struct dlm_msg *msg; @@ -1049,7 +1049,7 @@ static struct dlm_msg *dlm_midcomms_get_msg_3_2(struct dlm_mhandle *mh, int node dlm_fill_opts_header(opts, len, mh->seq); *ppc += sizeof(*opts); - mh->inner_hd = (const struct dlm_header *)*ppc; + mh->inner_p = (const union dlm_packet *)*ppc; return msg; } @@ -1127,7 +1127,7 @@ err: static void dlm_midcomms_commit_msg_3_2(struct dlm_mhandle *mh) { /* nexthdr chain for fast lookup */ - mh->opts->o_nextcmd = mh->inner_hd->h_cmd; + mh->opts->o_nextcmd = mh->inner_p->header.h_cmd; mh->committed = true; dlm_lowcomms_commit_msg(mh->msg); } -- 2.39.5