* [PATCH net 1/1] proc/sysctl: Fix the int overflow for jiffies conversion
@ 2017-03-30 0:39 ` gfree.wind
0 siblings, 0 replies; 2+ messages in thread
From: gfree.wind @ 2017-03-30 0:39 UTC (permalink / raw)
To: davem, netdev, linux-kernel, gfree.wind; +Cc: Gao Feng
From: Gao Feng <fgao@ikuai8.com>
The function do_proc_dointvec_jiffies_conv uses LONG_MX/HZ as the
max value to avoid overflow. But actually the *valp is int type, so
it still causes overflow.
For example,
echo 2147483647 > ./sys/net/ipv4/tcp_keepalive_time
Then,
cat ./sys/net/ipv4/tcp_keepalive_time
The output is "-1", it is not expected.
Now use INT_MAX/HZ as the max value instead LONG_MAX/HZ to fix it.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
---
kernel/sysctl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index acf0a5a..60474df 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2571,7 +2571,7 @@ static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
int write, void *data)
{
if (write) {
- if (*lvalp > LONG_MAX / HZ)
+ if (*lvalp > INT_MAX / HZ)
return 1;
*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
} else {
--
1.9.1
^ permalink raw reply related [flat|nested] 2+ messages in thread
* [PATCH net 1/1] proc/sysctl: Fix the int overflow for jiffies conversion
@ 2017-03-30 0:39 ` gfree.wind
0 siblings, 0 replies; 2+ messages in thread
From: gfree.wind @ 2017-03-30 0:39 UTC (permalink / raw)
To: davem, netdev, linux-kernel, gfree.wind; +Cc: Gao Feng
From: Gao Feng <fgao@ikuai8.com>
The function do_proc_dointvec_jiffies_conv uses LONG_MX/HZ as the
max value to avoid overflow. But actually the *valp is int type, so
it still causes overflow.
For example,
echo 2147483647 > ./sys/net/ipv4/tcp_keepalive_time
Then,
cat ./sys/net/ipv4/tcp_keepalive_time
The output is "-1", it is not expected.
Now use INT_MAX/HZ as the max value instead LONG_MAX/HZ to fix it.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
---
kernel/sysctl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index acf0a5a..60474df 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2571,7 +2571,7 @@ static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
int write, void *data)
{
if (write) {
- if (*lvalp > LONG_MAX / HZ)
+ if (*lvalp > INT_MAX / HZ)
return 1;
*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
} else {
--
1.9.1
^ permalink raw reply related [flat|nested] 2+ messages in thread
end of thread, other threads:[~2017-03-30 0:40 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-03-30 0:39 [PATCH net 1/1] proc/sysctl: Fix the int overflow for jiffies conversion gfree.wind
2017-03-30 0:39 ` gfree.wind
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.