4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Junwei Hu <hujunwei4@xxxxxxxxxx>
commit 1b90af292e71b20d03b837d39406acfbdc5d4b2a upstream.
The ipvs module parse the user buffer and save it to sysctl,
then check if the value is valid. invalid value occurs
over a period of time.
Here, I add a variable, struct ctl_table tmp, used to read
the value from the user buffer, and save only when it is valid.
I delete proc_do_sync_mode and use extra1/2 in table for the
proc_dointvec_minmax call.
Fixes: f73181c8288f ("ipvs: add support for sync threads")
Signed-off-by: Junwei Hu <hujunwei4@xxxxxxxxxx>
Acked-by: Julian Anastasov <ja@xxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
[Julian: Backport by changing SYSCTL_ZERO/SYSCTL_ONE to zero/one]
Signed-off-by: Julian Anastasov <ja@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netfilter/ipvs/ip_vs_ctl.c | 70 +++++++++++++++++++++--------------------
1 file changed, 36 insertions(+), 34 deletions(-)
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -1656,6 +1656,7 @@ static int ip_vs_zero_all(struct netns_i
#ifdef CONFIG_SYSCTL
static int zero;
+static int one = 1;
static int three = 3;
static int
@@ -1667,12 +1668,18 @@ proc_do_defense_mode(struct ctl_table *t
int val = *valp;
int rc;
- rc = proc_dointvec(table, write, buffer, lenp, ppos);
+ struct ctl_table tmp = {
+ .data = &val,
+ .maxlen = sizeof(int),
+ .mode = table->mode,
+ };
+
+ rc = proc_dointvec(&tmp, write, buffer, lenp, ppos);
if (write && (*valp != val)) {
- if ((*valp < 0) || (*valp > 3)) {
- /* Restore the correct value */
- *valp = val;
+ if (val < 0 || val > 3) {
+ rc = -EINVAL;
} else {
+ *valp = val;
update_defense_level(ipvs);
}
}
@@ -1686,33 +1693,20 @@ proc_do_sync_threshold(struct ctl_table
int *valp = table->data;
int val[2];
int rc;
+ struct ctl_table tmp = {
+ .data = &val,
+ .maxlen = table->maxlen,
+ .mode = table->mode,
+ };
- /* backup the value first */
memcpy(val, valp, sizeof(val));
-
- rc = proc_dointvec(table, write, buffer, lenp, ppos);
- if (write && (valp[0] < 0 || valp[1] < 0 ||
- (valp[0] >= valp[1] && valp[1]))) {
- /* Restore the correct value */
- memcpy(valp, val, sizeof(val));
- }
- return rc;
-}
-
-static int
-proc_do_sync_mode(struct ctl_table *table, int write,
- void __user *buffer, size_t *lenp, loff_t *ppos)
-{
- int *valp = table->data;
- int val = *valp;
- int rc;
-
- rc = proc_dointvec(table, write, buffer, lenp, ppos);
- if (write && (*valp != val)) {
- if ((*valp < 0) || (*valp > 1)) {
- /* Restore the correct value */
- *valp = val;
- }
+ rc = proc_dointvec(&tmp, write, buffer, lenp, ppos);
+ if (write) {
+ if (val[0] < 0 || val[1] < 0 ||
+ (val[0] >= val[1] && val[1]))
+ rc = -EINVAL;
+ else
+ memcpy(valp, val, sizeof(val));
}
return rc;
}
@@ -1725,12 +1719,18 @@ proc_do_sync_ports(struct ctl_table *tab
int val = *valp;
int rc;
- rc = proc_dointvec(table, write, buffer, lenp, ppos);
+ struct ctl_table tmp = {
+ .data = &val,
+ .maxlen = sizeof(int),
+ .mode = table->mode,
+ };
+
+ rc = proc_dointvec(&tmp, write, buffer, lenp, ppos);
if (write && (*valp != val)) {
- if (*valp < 1 || !is_power_of_2(*valp)) {
- /* Restore the correct value */
+ if (val < 1 || !is_power_of_2(val))
+ rc = -EINVAL;
+ else
*valp = val;
- }
}
return rc;
}
@@ -1790,7 +1790,9 @@ static struct ctl_table vs_vars[] = {
.procname = "sync_version",
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_do_sync_mode,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &one,
},
{
.procname = "sync_ports",
