This is a note to let you know that I've just added the patch titled
ipv6: Fix nexthop refcnt leak when creating ipv6 route info
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ipv6-fix-nexthop-refcnt-leak-when-creating-ipv6-route-info.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Mon 10 Aug 2020 02:07:44 PM CEST
From: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>
Date: Sat, 25 Jul 2020 16:02:18 +0800
Subject: ipv6: Fix nexthop refcnt leak when creating ipv6 route info
From: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>
[ Upstream commit 706ec919164622ff5ce822065472d0f30a9e9dd2 ]
ip6_route_info_create() invokes nexthop_get(), which increases the
refcount of the "nh".
When ip6_route_info_create() returns, local variable "nh" becomes
invalid, so the refcount should be decreased to keep refcount balanced.
The reference counting issue happens in one exception handling path of
ip6_route_info_create(). When nexthops can not be used with source
routing, the function forgets to decrease the refcnt increased by
nexthop_get(), causing a refcnt leak.
Fix this issue by pulling up the error source routing handling when
nexthops can not be used with source routing.
Fixes: f88d8ea67fbd ("ipv6: Plumb support for nexthop object in a fib6_info")
Signed-off-by: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>
Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx>
Reviewed-by: David Ahern <dsahern@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv6/route.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -3686,14 +3686,14 @@ static struct fib6_info *ip6_route_info_
rt->fib6_src.plen = cfg->fc_src_len;
#endif
if (nh) {
- if (!nexthop_get(nh)) {
- NL_SET_ERR_MSG(extack, "Nexthop has been deleted");
- goto out;
- }
if (rt->fib6_src.plen) {
NL_SET_ERR_MSG(extack, "Nexthops can not be used with source routing");
goto out;
}
+ if (!nexthop_get(nh)) {
+ NL_SET_ERR_MSG(extack, "Nexthop has been deleted");
+ goto out;
+ }
rt->nh = nh;
fib6_nh = nexthop_fib6_nh(rt->nh);
} else {
Patches currently in stable-queue which might be from xiyuyang19@xxxxxxxxxxxx are
queue-5.4/atm-fix-atm_dev-refcnt-leaks-in-atmtcp_remove_persis.patch
queue-5.4/ipv6-fix-nexthop-refcnt-leak-when-creating-ipv6-route-info.patch
