diff options
author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-18 20:26:42 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2022-07-20 12:14:49 +0300 |
commit | 9b55c20f83369dd54541d9ddbe3a018a8377f451 (patch) | |
tree | 47fb5876d7c291eda26016d3711002bfb19f9bf4 | |
parent | 8895a9c2ac76fb9d3922fed4fe092c8ec5e5cccc (diff) | |
download | linux-9b55c20f83369dd54541d9ddbe3a018a8377f451.tar.xz |
ip: Fix data-races around sysctl_ip_prot_sock.
sysctl_ip_prot_sock is accessed concurrently, and there is always a chance
of data-race. So, all readers and writers need some basic protection to
avoid load/store-tearing.
Fixes: 4548b683b781 ("Introduce a sysctl that modifies the value of PROT_SOCK.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | include/net/ip.h | 2 | ||||
-rw-r--r-- | net/ipv4/sysctl_net_ipv4.c | 6 |
2 files changed, 4 insertions, 4 deletions
diff --git a/include/net/ip.h b/include/net/ip.h index 4a15b6bcb4b8..1c979fd1904c 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -357,7 +357,7 @@ static inline bool sysctl_dev_name_is_allowed(const char *name) static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port) { - return port < net->ipv4.sysctl_ip_prot_sock; + return port < READ_ONCE(net->ipv4.sysctl_ip_prot_sock); } #else diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index 130e9c130311..5490c285668b 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -84,7 +84,7 @@ static int ipv4_local_port_range(struct ctl_table *table, int write, * port limit. */ if ((range[1] < range[0]) || - (range[0] < net->ipv4.sysctl_ip_prot_sock)) + (range[0] < READ_ONCE(net->ipv4.sysctl_ip_prot_sock))) ret = -EINVAL; else set_local_port_range(net, range); @@ -110,7 +110,7 @@ static int ipv4_privileged_ports(struct ctl_table *table, int write, .extra2 = &ip_privileged_port_max, }; - pports = net->ipv4.sysctl_ip_prot_sock; + pports = READ_ONCE(net->ipv4.sysctl_ip_prot_sock); ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); @@ -122,7 +122,7 @@ static int ipv4_privileged_ports(struct ctl_table *table, int write, if (range[0] < pports) ret = -EINVAL; else - net->ipv4.sysctl_ip_prot_sock = pports; + WRITE_ONCE(net->ipv4.sysctl_ip_prot_sock, pports); } return ret; |