This is a note to let you know that I've just added the patch titled
inet: ipmr: fix data-races
to the 6.12-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:
inet-ipmr-fix-data-races.patch
and it can be found in the queue-6.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 310c76e13c6913af38f83f306ac6a30b6d081ea4
Author: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Tue Jan 14 22:10:49 2025 +0000
inet: ipmr: fix data-races
[ Upstream commit 3440fa34ad99d471f1085bc2f4dedeaebc310261 ]
Following fields of 'struct mr_mfc' can be updated
concurrently (no lock protection) from ip_mr_forward()
and ip6_mr_forward()
- bytes
- pkt
- wrong_if
- lastuse
They also can be read from other functions.
Convert bytes, pkt and wrong_if to atomic_long_t,
and use READ_ONCE()/WRITE_ONCE() for lastuse.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reviewed-by: David Ahern <dsahern@xxxxxxxxxx>
Link: https://patch.msgid.link/20250114221049.1190631-1-edumazet@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c
index 69cd689dbc83e..5afe6b155ef0d 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c
@@ -1003,10 +1003,10 @@ static void mlxsw_sp_mr_route_stats_update(struct mlxsw_sp *mlxsw_sp,
mr->mr_ops->route_stats(mlxsw_sp, mr_route->route_priv, &packets,
&bytes);
- if (mr_route->mfc->mfc_un.res.pkt != packets)
- mr_route->mfc->mfc_un.res.lastuse = jiffies;
- mr_route->mfc->mfc_un.res.pkt = packets;
- mr_route->mfc->mfc_un.res.bytes = bytes;
+ if (atomic_long_read(&mr_route->mfc->mfc_un.res.pkt) != packets)
+ WRITE_ONCE(mr_route->mfc->mfc_un.res.lastuse, jiffies);
+ atomic_long_set(&mr_route->mfc->mfc_un.res.pkt, packets);
+ atomic_long_set(&mr_route->mfc->mfc_un.res.bytes, bytes);
}
static void mlxsw_sp_mr_stats_update(struct work_struct *work)
diff --git a/include/linux/mroute_base.h b/include/linux/mroute_base.h
index 9dd4bf1572553..58a2401e4b551 100644
--- a/include/linux/mroute_base.h
+++ b/include/linux/mroute_base.h
@@ -146,9 +146,9 @@ struct mr_mfc {
unsigned long last_assert;
int minvif;
int maxvif;
- unsigned long bytes;
- unsigned long pkt;
- unsigned long wrong_if;
+ atomic_long_t bytes;
+ atomic_long_t pkt;
+ atomic_long_t wrong_if;
unsigned long lastuse;
unsigned char ttls[MAXVIFS];
refcount_t refcount;
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 449a2ac40bdc0..de0d9cc7806a1 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -817,7 +817,7 @@ static void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache,
cache->mfc_un.res.maxvif = vifi + 1;
}
}
- cache->mfc_un.res.lastuse = jiffies;
+ WRITE_ONCE(cache->mfc_un.res.lastuse, jiffies);
}
static int vif_add(struct net *net, struct mr_table *mrt,
@@ -1667,9 +1667,9 @@ int ipmr_ioctl(struct sock *sk, int cmd, void *arg)
rcu_read_lock();
c = ipmr_cache_find(mrt, sr->src.s_addr, sr->grp.s_addr);
if (c) {
- sr->pktcnt = c->_c.mfc_un.res.pkt;
- sr->bytecnt = c->_c.mfc_un.res.bytes;
- sr->wrong_if = c->_c.mfc_un.res.wrong_if;
+ sr->pktcnt = atomic_long_read(&c->_c.mfc_un.res.pkt);
+ sr->bytecnt = atomic_long_read(&c->_c.mfc_un.res.bytes);
+ sr->wrong_if = atomic_long_read(&c->_c.mfc_un.res.wrong_if);
rcu_read_unlock();
return 0;
}
@@ -1739,9 +1739,9 @@ int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
rcu_read_lock();
c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
if (c) {
- sr.pktcnt = c->_c.mfc_un.res.pkt;
- sr.bytecnt = c->_c.mfc_un.res.bytes;
- sr.wrong_if = c->_c.mfc_un.res.wrong_if;
+ sr.pktcnt = atomic_long_read(&c->_c.mfc_un.res.pkt);
+ sr.bytecnt = atomic_long_read(&c->_c.mfc_un.res.bytes);
+ sr.wrong_if = atomic_long_read(&c->_c.mfc_un.res.wrong_if);
rcu_read_unlock();
if (copy_to_user(arg, &sr, sizeof(sr)))
@@ -1974,9 +1974,9 @@ static void ip_mr_forward(struct net *net, struct mr_table *mrt,
int vif, ct;
vif = c->_c.mfc_parent;
- c->_c.mfc_un.res.pkt++;
- c->_c.mfc_un.res.bytes += skb->len;
- c->_c.mfc_un.res.lastuse = jiffies;
+ atomic_long_inc(&c->_c.mfc_un.res.pkt);
+ atomic_long_add(skb->len, &c->_c.mfc_un.res.bytes);
+ WRITE_ONCE(c->_c.mfc_un.res.lastuse, jiffies);
if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
struct mfc_cache *cache_proxy;
@@ -2007,7 +2007,7 @@ static void ip_mr_forward(struct net *net, struct mr_table *mrt,
goto dont_forward;
}
- c->_c.mfc_un.res.wrong_if++;
+ atomic_long_inc(&c->_c.mfc_un.res.wrong_if);
if (true_vifi >= 0 && mrt->mroute_do_assert &&
/* pimsm uses asserts, when switching from RPT to SPT,
@@ -3015,9 +3015,9 @@ static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
if (it->cache != &mrt->mfc_unres_queue) {
seq_printf(seq, " %8lu %8lu %8lu",
- mfc->_c.mfc_un.res.pkt,
- mfc->_c.mfc_un.res.bytes,
- mfc->_c.mfc_un.res.wrong_if);
+ atomic_long_read(&mfc->_c.mfc_un.res.pkt),
+ atomic_long_read(&mfc->_c.mfc_un.res.bytes),
+ atomic_long_read(&mfc->_c.mfc_un.res.wrong_if));
for (n = mfc->_c.mfc_un.res.minvif;
n < mfc->_c.mfc_un.res.maxvif; n++) {
if (VIF_EXISTS(mrt, n) &&
diff --git a/net/ipv4/ipmr_base.c b/net/ipv4/ipmr_base.c
index f0af12a2f70bc..03b6eee407a24 100644
--- a/net/ipv4/ipmr_base.c
+++ b/net/ipv4/ipmr_base.c
@@ -263,9 +263,9 @@ int mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
lastuse = READ_ONCE(c->mfc_un.res.lastuse);
lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0;
- mfcs.mfcs_packets = c->mfc_un.res.pkt;
- mfcs.mfcs_bytes = c->mfc_un.res.bytes;
- mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
+ mfcs.mfcs_packets = atomic_long_read(&c->mfc_un.res.pkt);
+ mfcs.mfcs_bytes = atomic_long_read(&c->mfc_un.res.bytes);
+ mfcs.mfcs_wrong_if = atomic_long_read(&c->mfc_un.res.wrong_if);
if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) ||
nla_put_u64_64bit(skb, RTA_EXPIRES, jiffies_to_clock_t(lastuse),
RTA_PAD))
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index d5057401701c1..440048d609c37 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -506,9 +506,9 @@ static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
if (it->cache != &mrt->mfc_unres_queue) {
seq_printf(seq, " %8lu %8lu %8lu",
- mfc->_c.mfc_un.res.pkt,
- mfc->_c.mfc_un.res.bytes,
- mfc->_c.mfc_un.res.wrong_if);
+ atomic_long_read(&mfc->_c.mfc_un.res.pkt),
+ atomic_long_read(&mfc->_c.mfc_un.res.bytes),
+ atomic_long_read(&mfc->_c.mfc_un.res.wrong_if));
for (n = mfc->_c.mfc_un.res.minvif;
n < mfc->_c.mfc_un.res.maxvif; n++) {
if (VIF_EXISTS(mrt, n) &&
@@ -870,7 +870,7 @@ static void ip6mr_update_thresholds(struct mr_table *mrt,
cache->mfc_un.res.maxvif = vifi + 1;
}
}
- cache->mfc_un.res.lastuse = jiffies;
+ WRITE_ONCE(cache->mfc_un.res.lastuse, jiffies);
}
static int mif6_add(struct net *net, struct mr_table *mrt,
@@ -1928,9 +1928,9 @@ int ip6mr_ioctl(struct sock *sk, int cmd, void *arg)
c = ip6mr_cache_find(mrt, &sr->src.sin6_addr,
&sr->grp.sin6_addr);
if (c) {
- sr->pktcnt = c->_c.mfc_un.res.pkt;
- sr->bytecnt = c->_c.mfc_un.res.bytes;
- sr->wrong_if = c->_c.mfc_un.res.wrong_if;
+ sr->pktcnt = atomic_long_read(&c->_c.mfc_un.res.pkt);
+ sr->bytecnt = atomic_long_read(&c->_c.mfc_un.res.bytes);
+ sr->wrong_if = atomic_long_read(&c->_c.mfc_un.res.wrong_if);
rcu_read_unlock();
return 0;
}
@@ -2000,9 +2000,9 @@ int ip6mr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
rcu_read_lock();
c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
if (c) {
- sr.pktcnt = c->_c.mfc_un.res.pkt;
- sr.bytecnt = c->_c.mfc_un.res.bytes;
- sr.wrong_if = c->_c.mfc_un.res.wrong_if;
+ sr.pktcnt = atomic_long_read(&c->_c.mfc_un.res.pkt);
+ sr.bytecnt = atomic_long_read(&c->_c.mfc_un.res.bytes);
+ sr.wrong_if = atomic_long_read(&c->_c.mfc_un.res.wrong_if);
rcu_read_unlock();
if (copy_to_user(arg, &sr, sizeof(sr)))
@@ -2125,9 +2125,9 @@ static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
int true_vifi = ip6mr_find_vif(mrt, dev);
vif = c->_c.mfc_parent;
- c->_c.mfc_un.res.pkt++;
- c->_c.mfc_un.res.bytes += skb->len;
- c->_c.mfc_un.res.lastuse = jiffies;
+ atomic_long_inc(&c->_c.mfc_un.res.pkt);
+ atomic_long_add(skb->len, &c->_c.mfc_un.res.bytes);
+ WRITE_ONCE(c->_c.mfc_un.res.lastuse, jiffies);
if (ipv6_addr_any(&c->mf6c_origin) && true_vifi >= 0) {
struct mfc6_cache *cache_proxy;
@@ -2145,7 +2145,7 @@ static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
* Wrong interface: drop packet and (maybe) send PIM assert.
*/
if (rcu_access_pointer(mrt->vif_table[vif].dev) != dev) {
- c->_c.mfc_un.res.wrong_if++;
+ atomic_long_inc(&c->_c.mfc_un.res.wrong_if);
if (true_vifi >= 0 && mrt->mroute_do_assert &&
/* pimsm uses asserts, when switching from RPT to SPT,
