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| author | Liu Jian <liujian56@huawei.com> | 2023-09-07 10:57:09 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-09-08 08:02:17 +0100 |
| commit | ac28b1ec6135649b5d78b028e47264cb3ebca5ea (patch) | |
| tree | ac210b6f17cf9b989cdbb882caa60b9ee84e1b9c /net | |
| parent | 73be7fb14e83d24383f840a22f24d3ed222ca319 (diff) | |
| download | lwn-ac28b1ec6135649b5d78b028e47264cb3ebca5ea.tar.gz lwn-ac28b1ec6135649b5d78b028e47264cb3ebca5ea.zip | |
net: ipv4: fix one memleak in __inet_del_ifa()
I got the below warning when do fuzzing test:
unregister_netdevice: waiting for bond0 to become free. Usage count = 2
It can be repoduced via:
ip link add bond0 type bond
sysctl -w net.ipv4.conf.bond0.promote_secondaries=1
ip addr add 4.117.174.103/0 scope 0x40 dev bond0
ip addr add 192.168.100.111/255.255.255.254 scope 0 dev bond0
ip addr add 0.0.0.4/0 scope 0x40 secondary dev bond0
ip addr del 4.117.174.103/0 scope 0x40 dev bond0
ip link delete bond0 type bond
In this reproduction test case, an incorrect 'last_prim' is found in
__inet_del_ifa(), as a result, the secondary address(0.0.0.4/0 scope 0x40)
is lost. The memory of the secondary address is leaked and the reference of
in_device and net_device is leaked.
Fix this problem:
Look for 'last_prim' starting at location of the deleted IP and inserting
the promoted IP into the location of 'last_prim'.
Fixes: 0ff60a45678e ("[IPV4]: Fix secondary IP addresses after promotion")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/devinet.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 9cf64ee47dd2..ca0ff15dc8fa 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -355,14 +355,14 @@ static void __inet_del_ifa(struct in_device *in_dev, { struct in_ifaddr *promote = NULL; struct in_ifaddr *ifa, *ifa1; - struct in_ifaddr *last_prim; + struct in_ifaddr __rcu **last_prim; struct in_ifaddr *prev_prom = NULL; int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev); ASSERT_RTNL(); ifa1 = rtnl_dereference(*ifap); - last_prim = rtnl_dereference(in_dev->ifa_list); + last_prim = ifap; if (in_dev->dead) goto no_promotions; @@ -376,7 +376,7 @@ static void __inet_del_ifa(struct in_device *in_dev, while ((ifa = rtnl_dereference(*ifap1)) != NULL) { if (!(ifa->ifa_flags & IFA_F_SECONDARY) && ifa1->ifa_scope <= ifa->ifa_scope) - last_prim = ifa; + last_prim = &ifa->ifa_next; if (!(ifa->ifa_flags & IFA_F_SECONDARY) || ifa1->ifa_mask != ifa->ifa_mask || @@ -440,9 +440,9 @@ no_promotions: rcu_assign_pointer(prev_prom->ifa_next, next_sec); - last_sec = rtnl_dereference(last_prim->ifa_next); + last_sec = rtnl_dereference(*last_prim); rcu_assign_pointer(promote->ifa_next, last_sec); - rcu_assign_pointer(last_prim->ifa_next, promote); + rcu_assign_pointer(*last_prim, promote); } promote->ifa_flags &= ~IFA_F_SECONDARY; |