[PATCH 1/3] lightnvm: fix up nonsensical configure overrun checking

[Matias Bjørling]

From: Alan 

Instead of checking a constant 0 actually check the space available. Even
better remember to allow for the header and also check the right amount of
space is needed.

Signed-off-by: Alan Cox 
Signed-off-by: Matias Bjørling 
---
 drivers/lightnvm/core.c | 11 +--
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index c3d4b54..b53632d 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -868,20 +868,19 @@ static int nvm_configure_by_str_event(const char *val,
 
 static int nvm_configure_get(char *buf, const struct kernel_param *kp)
 {
-   int sz = 0;
-   char *buf_start = buf;
+   int sz;
struct nvm_dev *dev;
 
-   buf += sprintf(buf, "available devices:\n");
+   sz = sprintf(buf, "available devices:\n");
down_write(_lock);
list_for_each_entry(dev, _devices, devices) {
-   if (sz > 4095 - DISK_NAME_LEN)
+   if (sz > 4095 - DISK_NAME_LEN - 2)
break;
-   buf += sprintf(buf, " %32s\n", dev->name);
+   sz += sprintf(buf + sz, " %32s\n", dev->name);
}
up_write(_lock);
 
-   return buf - buf_start - 1;
+   return sz;
 }
 
 static const struct kernel_param_ops nvm_configure_by_str_event_param_ops = {
-- 
2.1.4

[PATCH 1/3] lightnvm: fix up nonsensical configure overrun checking

[Matias Bjørling]

From: Alan 

Instead of checking a constant 0 actually check the space available. Even
better remember to allow for the header and also check the right amount of
space is needed.

Signed-off-by: Alan Cox 
Signed-off-by: Matias Bjørling 
---
 drivers/lightnvm/core.c | 11 +--
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index c3d4b54..b53632d 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -868,20 +868,19 @@ static int nvm_configure_by_str_event(const char *val,
 
 static int nvm_configure_get(char *buf, const struct kernel_param *kp)
 {
-   int sz = 0;
-   char *buf_start = buf;
+   int sz;
struct nvm_dev *dev;
 
-   buf += sprintf(buf, "available devices:\n");
+   sz = sprintf(buf, "available devices:\n");
down_write(_lock);
list_for_each_entry(dev, _devices, devices) {
-   if (sz > 4095 - DISK_NAME_LEN)
+   if (sz > 4095 - DISK_NAME_LEN - 2)
break;
-   buf += sprintf(buf, " %32s\n", dev->name);
+   sz += sprintf(buf + sz, " %32s\n", dev->name);
}
up_write(_lock);
 
-   return buf - buf_start - 1;
+   return sz;
 }
 
 static const struct kernel_param_ops nvm_configure_by_str_event_param_ops = {
-- 
2.1.4