Replace 'sprintf' with 'scnprintf' to avoid overrun.
Signed-off-by: Yang Shen <[email protected]>
Reviewed-by: Zhou Wang <[email protected]>
---
drivers/crypto/hisilicon/zip/zip_main.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/crypto/hisilicon/zip/zip_main.c b/drivers/crypto/hisilicon/zip/zip_main.c
index df1a16f..1883d1b 100644
--- a/drivers/crypto/hisilicon/zip/zip_main.c
+++ b/drivers/crypto/hisilicon/zip/zip_main.c
@@ -428,7 +428,7 @@ static ssize_t hisi_zip_ctrl_debug_read(struct file *filp, char __user *buf,
return -EINVAL;
}
spin_unlock_irq(&file->lock);
- ret = sprintf(tbuf, "%u\n", val);
+ ret = scnprintf(tbuf, HZIP_BUF_SIZE, "%u\n", val);
return simple_read_from_buffer(buf, count, pos, tbuf, ret);
}
@@ -514,13 +514,16 @@ static int hisi_zip_core_debug_init(struct hisi_qm *qm)
struct debugfs_regset32 *regset;
struct dentry *tmp_d;
char buf[HZIP_BUF_SIZE];
- int i;
+ int i, ret;
for (i = 0; i < HZIP_CORE_NUM; i++) {
if (i < HZIP_COMP_CORE_NUM)
- sprintf(buf, "comp_core%d", i);
+ ret = scnprintf(buf, HZIP_BUF_SIZE, "comp_core%d", i);
else
- sprintf(buf, "decomp_core%d", i - HZIP_COMP_CORE_NUM);
+ ret = scnprintf(buf, HZIP_BUF_SIZE, "decomp_core%d",
+ i - HZIP_COMP_CORE_NUM);
+ if (!ret)
+ return -ENOMEM;
regset = devm_kzalloc(dev, sizeof(*regset), GFP_KERNEL);
if (!regset)
--
2.7.4
From: Yang Shen
> Sent: 24 August 2020 04:12
>
> Replace 'sprintf' with 'scnprintf' to avoid overrun.
>
> Signed-off-by: Yang Shen <[email protected]>
> Reviewed-by: Zhou Wang <[email protected]>
> ---
> drivers/crypto/hisilicon/zip/zip_main.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/crypto/hisilicon/zip/zip_main.c b/drivers/crypto/hisilicon/zip/zip_main.c
> index df1a16f..1883d1b 100644
> --- a/drivers/crypto/hisilicon/zip/zip_main.c
> +++ b/drivers/crypto/hisilicon/zip/zip_main.c
> @@ -428,7 +428,7 @@ static ssize_t hisi_zip_ctrl_debug_read(struct file *filp, char __user *buf,
> return -EINVAL;
> }
> spin_unlock_irq(&file->lock);
> - ret = sprintf(tbuf, "%u\n", val);
> + ret = scnprintf(tbuf, HZIP_BUF_SIZE, "%u\n", val);
Should that be sizeof (tbuf).
> return simple_read_from_buffer(buf, count, pos, tbuf, ret);
> }
>
> @@ -514,13 +514,16 @@ static int hisi_zip_core_debug_init(struct hisi_qm *qm)
> struct debugfs_regset32 *regset;
> struct dentry *tmp_d;
> char buf[HZIP_BUF_SIZE];
> - int i;
> + int i, ret;
>
> for (i = 0; i < HZIP_CORE_NUM; i++) {
> if (i < HZIP_COMP_CORE_NUM)
> - sprintf(buf, "comp_core%d", i);
> + ret = scnprintf(buf, HZIP_BUF_SIZE, "comp_core%d", i);
> else
> - sprintf(buf, "decomp_core%d", i - HZIP_COMP_CORE_NUM);
> + ret = scnprintf(buf, HZIP_BUF_SIZE, "decomp_core%d",
> + i - HZIP_COMP_CORE_NUM);
> + if (!ret)
> + return -ENOMEM;
and that is just so wrong - did you even try to test
the 'buffer too small' code path?
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
On 2020/9/4 15:40, Herbert Xu wrote:
> On Wed, Aug 26, 2020 at 04:56:40PM +0800, shenyang (M) wrote:
>>
>>>> @@ -514,13 +514,16 @@ static int hisi_zip_core_debug_init(struct hisi_qm *qm)
>>>> struct debugfs_regset32 *regset;
>>>> struct dentry *tmp_d;
>>>> char buf[HZIP_BUF_SIZE];
>>>> - int i;
>>>> + int i, ret;
>>>>
>>>> for (i = 0; i < HZIP_CORE_NUM; i++) {
>>>> if (i < HZIP_COMP_CORE_NUM)
>>>> - sprintf(buf, "comp_core%d", i);
>>>> + ret = scnprintf(buf, HZIP_BUF_SIZE, "comp_core%d", i);
>>>> else
>>>> - sprintf(buf, "decomp_core%d", i - HZIP_COMP_CORE_NUM);
>>>> + ret = scnprintf(buf, HZIP_BUF_SIZE, "decomp_core%d",
>>>> + i - HZIP_COMP_CORE_NUM);
>>>> + if (!ret)
>>>> + return -ENOMEM;
>>>
>>> and that is just so wrong - did you even try to test
>>> the 'buffer too small' code path?
>>
>> Do you means the check is unnecessary?
>
> No he's saying that your patch does the wrong thing when the string
> is truncated.
>
> Also ENOMEM is a strange error for that case.
>
> Cheers,
>
Here 'HZIP_BUF_SIZE' is 22, so the buf is enough for the string.
The check for the return is really unnecessary, I will remove it in the
next version.
Thanks,
Yang