[PATCH] xfrm: Use spin_lock_bh() in xfrm_input()

From: Zhang Yiqun
Date: Mon Dec 18 2023 - 03:43:41 EST


This patch is to change spin_lock() into spin_lock_bh(), which can
disable bottem half in calling. If we leave this as spin_lock(),
it may stuck in a deadlock, because the callback in bottem half in
crypto driver will also call xfrm_input() again.

Signed-off-by: Zhang Yiqun <zhangyiqun@xxxxxxxxxxxxxx>
---
net/xfrm/xfrm_input.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index bd4ce21d76d7..f4cd46d73b1e 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -581,7 +581,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
}

lock:
- spin_lock(&x->lock);
+ spin_lock_bh(&x->lock);

if (unlikely(x->km.state != XFRM_STATE_VALID)) {
if (x->km.state == XFRM_STATE_ACQ)
@@ -607,7 +607,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
goto drop_unlock;
}

- spin_unlock(&x->lock);
+ spin_unlock_bh(&x->lock);

if (xfrm_tunnel_check(skb, x, family)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
--
2.17.1