[PATCH ipsec] xfrm: Fix error reporting in xfrm_state_construct.

[PATCH ipsec] xfrm: Fix error reporting in xfrm_state_construct.

[Steffen Klassert]

When memory allocation for XFRMA_ENCAP or XFRMA_COADDR fails,
the error will not be reported because the -ENOMEM assignment
to the err variable is overwritten before. Fix this by moving
these two in front of the function so that memory allocation
failures will be reported.

Reported-by: Tobias Brunner <tobias@strongswan.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_user.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 5a0ef4361e43..817e714dedea 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -580,6 +580,20 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 
 	copy_from_user_state(x, p);
 
+	if (attrs[XFRMA_ENCAP]) {
+		x->encap = kmemdup(nla_data(attrs[XFRMA_ENCAP]),
+				   sizeof(*x->encap), GFP_KERNEL);
+		if (x->encap == NULL)
+			goto error;
+	}
+
+	if (attrs[XFRMA_COADDR]) {
+		x->coaddr = kmemdup(nla_data(attrs[XFRMA_COADDR]),
+				    sizeof(*x->coaddr), GFP_KERNEL);
+		if (x->coaddr == NULL)
+			goto error;
+	}
+
 	if (attrs[XFRMA_SA_EXTRA_FLAGS])
 		x->props.extra_flags = nla_get_u32(attrs[XFRMA_SA_EXTRA_FLAGS]);
 
@@ -600,23 +614,9 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 				   attrs[XFRMA_ALG_COMP])))
 		goto error;
 
-	if (attrs[XFRMA_ENCAP]) {
-		x->encap = kmemdup(nla_data(attrs[XFRMA_ENCAP]),
-				   sizeof(*x->encap), GFP_KERNEL);
-		if (x->encap == NULL)
-			goto error;
-	}
-
 	if (attrs[XFRMA_TFCPAD])
 		x->tfcpad = nla_get_u32(attrs[XFRMA_TFCPAD]);
 
-	if (attrs[XFRMA_COADDR]) {
-		x->coaddr = kmemdup(nla_data(attrs[XFRMA_COADDR]),
-				    sizeof(*x->coaddr), GFP_KERNEL);
-		if (x->coaddr == NULL)
-			goto error;
-	}
-
 	xfrm_mark_get(attrs, &x->mark);
 
 	xfrm_smark_init(attrs, &x->props.smark);
-- 
2.25.1

Re: [PATCH ipsec] xfrm: Fix error reporting in xfrm_state_construct.

[Steffen Klassert]

On Mon, Jun 07, 2021 at 03:21:49PM +0200, Steffen Klassert wrote:
> When memory allocation for XFRMA_ENCAP or XFRMA_COADDR fails,
> the error will not be reported because the -ENOMEM assignment
> to the err variable is overwritten before. Fix this by moving
> these two in front of the function so that memory allocation
> failures will be reported.
> 
> Reported-by: Tobias Brunner <tobias@strongswan.org>
> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
> ---

Now applied to the ipsec tree.