diff mbox series

[1/1] target: Make sure no zero value in the buffer

Message ID 20201203114040.12656-1-ruc_zhangxiaohui@163.com
State New
Headers show
Series [1/1] target: Make sure no zero value in the buffer | expand

Commit Message

Xiaohui Zhang Dec. 3, 2020, 11:40 a.m. UTC
From: Zhang Xiaohui <ruc_zhangxiaohui@163.com>

The fix makes sure no zero value in the buffer, by comparing the
strlen() of the original buffer with the size variable.

Signed-off-by: Zhang Xiaohui <ruc_zhangxiaohui@163.com>
---
 drivers/target/target_core_iblock.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

Bodo Stroesser Dec. 6, 2020, 6:55 p.m. UTC | #1
On 03.12.20 12:40, Xiaohui Zhang wrote:
> From: Zhang Xiaohui <ruc_zhangxiaohui@163.com>

> 

> The fix makes sure no zero value in the buffer, by comparing the

> strlen() of the original buffer with the size variable.


What problem do you want to fix here?
I think, presently iblock_set_configfs_dev_params() just ignores input after a possible zero byte, which AFAICS is the usual way to handle such 'abnormal' input.

Of course, strictly taken it is a bug to return 'count' without having processed count bytes. OTOH, iblock_set_configfs_dev_params also silently ignores unknown parameter strings.
If you want to have strict error handling in such sys- or config-FS callbacks, you have to do a lot of work ...

> 

> Signed-off-by: Zhang Xiaohui <ruc_zhangxiaohui@163.com>

> ---

>   drivers/target/target_core_iblock.c | 2 ++

>   1 file changed, 2 insertions(+)

> 

> diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c

> index f2bd2e207..b23e92449 100644

> --- a/drivers/target/target_core_iblock.c

> +++ b/drivers/target/target_core_iblock.c

> @@ -537,6 +537,8 @@ static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,

>   	int ret = 0, token;

>   	unsigned long tmp_readonly;

>   

> +	if (strlen(page) < count)

> +		return -EOVERFLOW;

>   	opts = kstrdup(page, GFP_KERNEL);

>   	if (!opts)

>   		return -ENOMEM;

>
diff mbox series

Patch

diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index f2bd2e207..b23e92449 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -537,6 +537,8 @@  static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
 	int ret = 0, token;
 	unsigned long tmp_readonly;
 
+	if (strlen(page) < count)
+		return -EOVERFLOW;
 	opts = kstrdup(page, GFP_KERNEL);
 	if (!opts)
 		return -ENOMEM;