From: Pavel Emelyanov <xemul@openvz.org>
Date: Fri, 14 Nov 2008 22:51:45 +0000 (-0800)
Subject: scm: fix scm_fp_list->list initialization made in wrong place
X-Git-Tag: firefly_0821_release~16788^2~16
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=5421ae0153b4ba0469967cfd8de96144e3bf3979;p=firefly-linux-kernel-4.4.55.git

scm: fix scm_fp_list->list initialization made in wrong place

This is the next page of the scm recursion story (the commit
f8d570a4 net: Fix recursive descent in __scm_destroy()).

In function scm_fp_dup(), the INIT_LIST_HEAD(&fpl->list) of newly
created fpl is done *before* the subsequent memcpy from the old
structure and thus the freshly initialized list is overwritten.

But that's OK, since this initialization is not required at all,
since the fpl->list is list_add-ed at the destruction time in any
case (and is unused in other code), so I propose to drop both
initializations, rather than moving it after the memcpy.

Please, correct me if I miss something significant.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/core/scm.c b/net/core/scm.c
index ab242cc1acca..b12303dd39d9 100644
--- a/net/core/scm.c
+++ b/net/core/scm.c
@@ -75,7 +75,6 @@ static int scm_fp_copy(struct cmsghdr *cmsg, struct scm_fp_list **fplp)
 		if (!fpl)
 			return -ENOMEM;
 		*fplp = fpl;
-		INIT_LIST_HEAD(&fpl->list);
 		fpl->count = 0;
 	}
 	fpp = &fpl->fp[fpl->count];
@@ -301,7 +300,6 @@ struct scm_fp_list *scm_fp_dup(struct scm_fp_list *fpl)
 
 	new_fpl = kmalloc(sizeof(*fpl), GFP_KERNEL);
 	if (new_fpl) {
-		INIT_LIST_HEAD(&new_fpl->list);
 		for (i=fpl->count-1; i>=0; i--)
 			get_file(fpl->fp[i]);
 		memcpy(new_fpl, fpl, sizeof(*fpl));