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Diffstat (limited to '')
| -rw-r--r-- | debian/patches-rt/0203-net-add-a-lock-around-icmp_sk.patch | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/debian/patches-rt/0203-net-add-a-lock-around-icmp_sk.patch b/debian/patches-rt/0203-net-add-a-lock-around-icmp_sk.patch new file mode 100644 index 000000000..fa2ad051e --- /dev/null +++ b/debian/patches-rt/0203-net-add-a-lock-around-icmp_sk.patch @@ -0,0 +1,65 @@ +From 95179968fe9e7b7b6484facb14b8ac985cc0d779 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Wed, 31 Aug 2016 17:54:09 +0200 +Subject: [PATCH 203/347] net: add a lock around icmp_sk() +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz + +It looks like the this_cpu_ptr() access in icmp_sk() is protected with +local_bh_disable(). To avoid missing serialization in -RT I am adding +here a local lock. No crash has been observed, this is just precaution. + +Cc: stable-rt@vger.kernel.org +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + net/ipv4/icmp.c | 8 ++++++++ + 1 file changed, 8 insertions(+) + +diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c +index fe10a565b7d8..d35719e08aef 100644 +--- a/net/ipv4/icmp.c ++++ b/net/ipv4/icmp.c +@@ -77,6 +77,7 @@ + #include <linux/string.h> + #include <linux/netfilter_ipv4.h> + #include <linux/slab.h> ++#include <linux/locallock.h> + #include <net/snmp.h> + #include <net/ip.h> + #include <net/route.h> +@@ -204,6 +205,8 @@ static const struct icmp_control icmp_pointers[NR_ICMP_TYPES+1]; + * + * On SMP we have one ICMP socket per-cpu. + */ ++static DEFINE_LOCAL_IRQ_LOCK(icmp_sk_lock); ++ + static struct sock *icmp_sk(struct net *net) + { + return *this_cpu_ptr(net->ipv4.icmp_sk); +@@ -214,12 +217,16 @@ static inline struct sock *icmp_xmit_lock(struct net *net) + { + struct sock *sk; + ++ if (!local_trylock(icmp_sk_lock)) ++ return NULL; ++ + sk = icmp_sk(net); + + if (unlikely(!spin_trylock(&sk->sk_lock.slock))) { + /* This can happen if the output path signals a + * dst_link_failure() for an outgoing ICMP packet. + */ ++ local_unlock(icmp_sk_lock); + return NULL; + } + return sk; +@@ -228,6 +235,7 @@ static inline struct sock *icmp_xmit_lock(struct net *net) + static inline void icmp_xmit_unlock(struct sock *sk) + { + spin_unlock(&sk->sk_lock.slock); ++ local_unlock(icmp_sk_lock); + } + + int sysctl_icmp_msgs_per_sec __read_mostly = 1000; +-- +2.36.1 + |