From 4f3fdf3bc59cafd14c3bc2c2369efad34c7aa8b5 Mon Sep 17 00:00:00 2001 From: wangweidong Date: Wed, 11 Dec 2013 09:50:39 +0800 Subject: sctp: add check rto_min and rto_max in sysctl rto_min should be smaller than rto_max while rto_max should be larger than rto_min. Add two proc_handler for the checking. Suggested-by: Vlad Yasevich Signed-off-by: Wang Weidong Acked-by: Vlad Yasevich Signed-off-by: David S. Miller --- net/sctp/sysctl.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 65 insertions(+), 4 deletions(-) diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c index 6b36561a1b3b..43b5e3243871 100644 --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -61,6 +61,13 @@ static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, void __user *buffer, size_t *lenp, loff_t *ppos); +static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos); +static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos); + static struct ctl_table sctp_table[] = { { .procname = "sctp_mem", @@ -102,17 +109,17 @@ static struct ctl_table sctp_net_table[] = { .data = &init_net.sctp.rto_min, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = proc_sctp_do_rto_min, .extra1 = &one, - .extra2 = &timer_max + .extra2 = &init_net.sctp.rto_max }, { .procname = "rto_max", .data = &init_net.sctp.rto_max, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &one, + .proc_handler = proc_sctp_do_rto_max, + .extra1 = &init_net.sctp.rto_min, .extra2 = &timer_max }, { @@ -342,6 +349,60 @@ static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, return ret; } +static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + struct net *net = current->nsproxy->net_ns; + int new_value; + struct ctl_table tbl; + unsigned int min = *(unsigned int *) ctl->extra1; + unsigned int max = *(unsigned int *) ctl->extra2; + int ret; + + memset(&tbl, 0, sizeof(struct ctl_table)); + tbl.maxlen = sizeof(unsigned int); + + if (write) + tbl.data = &new_value; + else + tbl.data = &net->sctp.rto_min; + ret = proc_dointvec(&tbl, write, buffer, lenp, ppos); + if (write) { + if (ret || new_value > max || new_value < min) + return -EINVAL; + net->sctp.rto_min = new_value; + } + return ret; +} + +static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + struct net *net = current->nsproxy->net_ns; + int new_value; + struct ctl_table tbl; + unsigned int min = *(unsigned int *) ctl->extra1; + unsigned int max = *(unsigned int *) ctl->extra2; + int ret; + + memset(&tbl, 0, sizeof(struct ctl_table)); + tbl.maxlen = sizeof(unsigned int); + + if (write) + tbl.data = &new_value; + else + tbl.data = &net->sctp.rto_max; + ret = proc_dointvec(&tbl, write, buffer, lenp, ppos); + if (write) { + if (ret || new_value > max || new_value < min) + return -EINVAL; + net->sctp.rto_max = new_value; + } + return ret; +} + int sctp_sysctl_net_register(struct net *net) { struct ctl_table *table; -- cgit v1.2.3-59-g8ed1b