inet: ipmr: fix data-races

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: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250114221049.1190631-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Eric Dumazet 2025-01-14 22:10:49 +00:00 committed by Jakub Kicinski
parent bf38a2f766
commit 3440fa34ad
5 changed files with 38 additions and 38 deletions

View File

@ -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, mr->mr_ops->route_stats(mlxsw_sp, mr_route->route_priv, &packets,
&bytes); &bytes);
if (mr_route->mfc->mfc_un.res.pkt != packets) if (atomic_long_read(&mr_route->mfc->mfc_un.res.pkt) != packets)
mr_route->mfc->mfc_un.res.lastuse = jiffies; WRITE_ONCE(mr_route->mfc->mfc_un.res.lastuse, jiffies);
mr_route->mfc->mfc_un.res.pkt = packets; atomic_long_set(&mr_route->mfc->mfc_un.res.pkt, packets);
mr_route->mfc->mfc_un.res.bytes = bytes; atomic_long_set(&mr_route->mfc->mfc_un.res.bytes, bytes);
} }
static void mlxsw_sp_mr_stats_update(struct work_struct *work) static void mlxsw_sp_mr_stats_update(struct work_struct *work)

View File

@ -146,9 +146,9 @@ struct mr_mfc {
unsigned long last_assert; unsigned long last_assert;
int minvif; int minvif;
int maxvif; int maxvif;
unsigned long bytes; atomic_long_t bytes;
unsigned long pkt; atomic_long_t pkt;
unsigned long wrong_if; atomic_long_t wrong_if;
unsigned long lastuse; unsigned long lastuse;
unsigned char ttls[MAXVIFS]; unsigned char ttls[MAXVIFS];
refcount_t refcount; refcount_t refcount;

View File

@ -831,7 +831,7 @@ static void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache,
cache->mfc_un.res.maxvif = vifi + 1; cache->mfc_un.res.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, static int vif_add(struct net *net, struct mr_table *mrt,
@ -1681,9 +1681,9 @@ int ipmr_ioctl(struct sock *sk, int cmd, void *arg)
rcu_read_lock(); rcu_read_lock();
c = ipmr_cache_find(mrt, sr->src.s_addr, sr->grp.s_addr); c = ipmr_cache_find(mrt, sr->src.s_addr, sr->grp.s_addr);
if (c) { if (c) {
sr->pktcnt = c->_c.mfc_un.res.pkt; sr->pktcnt = atomic_long_read(&c->_c.mfc_un.res.pkt);
sr->bytecnt = c->_c.mfc_un.res.bytes; sr->bytecnt = atomic_long_read(&c->_c.mfc_un.res.bytes);
sr->wrong_if = c->_c.mfc_un.res.wrong_if; sr->wrong_if = atomic_long_read(&c->_c.mfc_un.res.wrong_if);
rcu_read_unlock(); rcu_read_unlock();
return 0; return 0;
} }
@ -1753,9 +1753,9 @@ int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
rcu_read_lock(); rcu_read_lock();
c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr); c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
if (c) { if (c) {
sr.pktcnt = c->_c.mfc_un.res.pkt; sr.pktcnt = atomic_long_read(&c->_c.mfc_un.res.pkt);
sr.bytecnt = c->_c.mfc_un.res.bytes; sr.bytecnt = atomic_long_read(&c->_c.mfc_un.res.bytes);
sr.wrong_if = c->_c.mfc_un.res.wrong_if; sr.wrong_if = atomic_long_read(&c->_c.mfc_un.res.wrong_if);
rcu_read_unlock(); rcu_read_unlock();
if (copy_to_user(arg, &sr, sizeof(sr))) if (copy_to_user(arg, &sr, sizeof(sr)))
@ -1988,9 +1988,9 @@ static void ip_mr_forward(struct net *net, struct mr_table *mrt,
int vif, ct; int vif, ct;
vif = c->_c.mfc_parent; vif = c->_c.mfc_parent;
c->_c.mfc_un.res.pkt++; atomic_long_inc(&c->_c.mfc_un.res.pkt);
c->_c.mfc_un.res.bytes += skb->len; atomic_long_add(skb->len, &c->_c.mfc_un.res.bytes);
c->_c.mfc_un.res.lastuse = jiffies; WRITE_ONCE(c->_c.mfc_un.res.lastuse, jiffies);
if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) { if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
struct mfc_cache *cache_proxy; struct mfc_cache *cache_proxy;
@ -2021,7 +2021,7 @@ static void ip_mr_forward(struct net *net, struct mr_table *mrt,
goto dont_forward; 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 && if (true_vifi >= 0 && mrt->mroute_do_assert &&
/* pimsm uses asserts, when switching from RPT to SPT, /* pimsm uses asserts, when switching from RPT to SPT,
@ -3029,9 +3029,9 @@ static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
if (it->cache != &mrt->mfc_unres_queue) { if (it->cache != &mrt->mfc_unres_queue) {
seq_printf(seq, " %8lu %8lu %8lu", seq_printf(seq, " %8lu %8lu %8lu",
mfc->_c.mfc_un.res.pkt, atomic_long_read(&mfc->_c.mfc_un.res.pkt),
mfc->_c.mfc_un.res.bytes, atomic_long_read(&mfc->_c.mfc_un.res.bytes),
mfc->_c.mfc_un.res.wrong_if); atomic_long_read(&mfc->_c.mfc_un.res.wrong_if));
for (n = mfc->_c.mfc_un.res.minvif; for (n = mfc->_c.mfc_un.res.minvif;
n < mfc->_c.mfc_un.res.maxvif; n++) { n < mfc->_c.mfc_un.res.maxvif; n++) {
if (VIF_EXISTS(mrt, n) && if (VIF_EXISTS(mrt, n) &&

View File

@ -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 = READ_ONCE(c->mfc_un.res.lastuse);
lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0; lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0;
mfcs.mfcs_packets = c->mfc_un.res.pkt; mfcs.mfcs_packets = atomic_long_read(&c->mfc_un.res.pkt);
mfcs.mfcs_bytes = c->mfc_un.res.bytes; mfcs.mfcs_bytes = atomic_long_read(&c->mfc_un.res.bytes);
mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if; 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) || 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), nla_put_u64_64bit(skb, RTA_EXPIRES, jiffies_to_clock_t(lastuse),
RTA_PAD)) RTA_PAD))

View File

@ -520,9 +520,9 @@ static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
if (it->cache != &mrt->mfc_unres_queue) { if (it->cache != &mrt->mfc_unres_queue) {
seq_printf(seq, " %8lu %8lu %8lu", seq_printf(seq, " %8lu %8lu %8lu",
mfc->_c.mfc_un.res.pkt, atomic_long_read(&mfc->_c.mfc_un.res.pkt),
mfc->_c.mfc_un.res.bytes, atomic_long_read(&mfc->_c.mfc_un.res.bytes),
mfc->_c.mfc_un.res.wrong_if); atomic_long_read(&mfc->_c.mfc_un.res.wrong_if));
for (n = mfc->_c.mfc_un.res.minvif; for (n = mfc->_c.mfc_un.res.minvif;
n < mfc->_c.mfc_un.res.maxvif; n++) { n < mfc->_c.mfc_un.res.maxvif; n++) {
if (VIF_EXISTS(mrt, n) && if (VIF_EXISTS(mrt, n) &&
@ -884,7 +884,7 @@ static void ip6mr_update_thresholds(struct mr_table *mrt,
cache->mfc_un.res.maxvif = vifi + 1; 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, static int mif6_add(struct net *net, struct mr_table *mrt,
@ -1945,9 +1945,9 @@ int ip6mr_ioctl(struct sock *sk, int cmd, void *arg)
c = ip6mr_cache_find(mrt, &sr->src.sin6_addr, c = ip6mr_cache_find(mrt, &sr->src.sin6_addr,
&sr->grp.sin6_addr); &sr->grp.sin6_addr);
if (c) { if (c) {
sr->pktcnt = c->_c.mfc_un.res.pkt; sr->pktcnt = atomic_long_read(&c->_c.mfc_un.res.pkt);
sr->bytecnt = c->_c.mfc_un.res.bytes; sr->bytecnt = atomic_long_read(&c->_c.mfc_un.res.bytes);
sr->wrong_if = c->_c.mfc_un.res.wrong_if; sr->wrong_if = atomic_long_read(&c->_c.mfc_un.res.wrong_if);
rcu_read_unlock(); rcu_read_unlock();
return 0; return 0;
} }
@ -2017,9 +2017,9 @@ int ip6mr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
rcu_read_lock(); rcu_read_lock();
c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr); c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
if (c) { if (c) {
sr.pktcnt = c->_c.mfc_un.res.pkt; sr.pktcnt = atomic_long_read(&c->_c.mfc_un.res.pkt);
sr.bytecnt = c->_c.mfc_un.res.bytes; sr.bytecnt = atomic_long_read(&c->_c.mfc_un.res.bytes);
sr.wrong_if = c->_c.mfc_un.res.wrong_if; sr.wrong_if = atomic_long_read(&c->_c.mfc_un.res.wrong_if);
rcu_read_unlock(); rcu_read_unlock();
if (copy_to_user(arg, &sr, sizeof(sr))) if (copy_to_user(arg, &sr, sizeof(sr)))
@ -2142,9 +2142,9 @@ static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
int true_vifi = ip6mr_find_vif(mrt, dev); int true_vifi = ip6mr_find_vif(mrt, dev);
vif = c->_c.mfc_parent; vif = c->_c.mfc_parent;
c->_c.mfc_un.res.pkt++; atomic_long_inc(&c->_c.mfc_un.res.pkt);
c->_c.mfc_un.res.bytes += skb->len; atomic_long_add(skb->len, &c->_c.mfc_un.res.bytes);
c->_c.mfc_un.res.lastuse = jiffies; WRITE_ONCE(c->_c.mfc_un.res.lastuse, jiffies);
if (ipv6_addr_any(&c->mf6c_origin) && true_vifi >= 0) { if (ipv6_addr_any(&c->mf6c_origin) && true_vifi >= 0) {
struct mfc6_cache *cache_proxy; struct mfc6_cache *cache_proxy;
@ -2162,7 +2162,7 @@ static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
* Wrong interface: drop packet and (maybe) send PIM assert. * Wrong interface: drop packet and (maybe) send PIM assert.
*/ */
if (rcu_access_pointer(mrt->vif_table[vif].dev) != dev) { 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 && if (true_vifi >= 0 && mrt->mroute_do_assert &&
/* pimsm uses asserts, when switching from RPT to SPT, /* pimsm uses asserts, when switching from RPT to SPT,