From 4177e4960594f7e6ae2ae787667b1788178cf32c Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 7 Dec 2021 11:32:03 -0800 Subject: [PATCH] xfrm: use net device refcount tracker helpers xfrm4_fill_dst() and xfrm6_fill_dst() build dst, getting a device reference that will likely be released by standard dst_release() code. We have to track these references or risk a warning if CONFIG_NET_DEV_REFCNT_TRACKER=y Note to XFRM maintainers : Error path in xfrm6_fill_dst() releases the reference, but does not clear xdst->u.dst.dev, so I wonder if this could lead to double dev_put() in some cases, where a dst_release() _is_ called by the callers in their error path. This extra dev_put() was added in commit 84c4a9dfbf430 ("xfrm6: release dev before returning error") Fixes: 9038c320001d ("net: dst: add net device refcount tracking to dst_entry") Signed-off-by: Eric Dumazet Cc: Cong Wang Acked-by: Steffen Klassert Link: https://lore.kernel.org/r/20211207193203.2706158-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski --- net/ipv4/xfrm4_policy.c | 2 +- net/ipv6/xfrm6_policy.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c index 9ebd54752e03..9e83bcb6bc99 100644 --- a/net/ipv4/xfrm4_policy.c +++ b/net/ipv4/xfrm4_policy.c @@ -77,7 +77,7 @@ static int xfrm4_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, xdst->u.rt.rt_iif = fl4->flowi4_iif; xdst->u.dst.dev = dev; - dev_hold(dev); + dev_hold_track(dev, &xdst->u.dst.dev_tracker, GFP_ATOMIC); /* Sheit... I remember I did this right. Apparently, * it was magically lost, so this code needs audit */ diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c index af7a4b8b1e9c..fad687ee6dd8 100644 --- a/net/ipv6/xfrm6_policy.c +++ b/net/ipv6/xfrm6_policy.c @@ -74,11 +74,11 @@ static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, struct rt6_info *rt = (struct rt6_info *)xdst->route; xdst->u.dst.dev = dev; - dev_hold(dev); + dev_hold_track(dev, &xdst->u.dst.dev_tracker, GFP_ATOMIC); xdst->u.rt6.rt6i_idev = in6_dev_get(dev); if (!xdst->u.rt6.rt6i_idev) { - dev_put(dev); + dev_put_track(dev, &xdst->u.dst.dev_tracker); return -ENODEV; } -- 2.11.0