2023-03-25 08:37:10

by Wei Chen

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Subject: [PATCH] wireless: rtlwifi: fix incorrect error codes in rtl_debugfs_set_write_rfreg()

If there is a failure during copy_from_user or user-provided data buffer
is invalid, rtl_debugfs_set_write_rfreg should return negative error code
instead of a positive value count.

Fix this bug by returning correct error code. Moreover, the check of buffer
against null is removed since it will be handled by copy_from_user.

Signed-off-by: Wei Chen <[email protected]>
---
drivers/net/wireless/realtek/rtlwifi/debug.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtlwifi/debug.c b/drivers/net/wireless/realtek/rtlwifi/debug.c
index 3e7f9b4f1f19..9eb26dfe4ca9 100644
--- a/drivers/net/wireless/realtek/rtlwifi/debug.c
+++ b/drivers/net/wireless/realtek/rtlwifi/debug.c
@@ -375,8 +375,8 @@ static ssize_t rtl_debugfs_set_write_rfreg(struct file *filp,

tmp_len = (count > sizeof(tmp) - 1 ? sizeof(tmp) - 1 : count);

- if (!buffer || copy_from_user(tmp, buffer, tmp_len))
- return count;
+ if (copy_from_user(tmp, buffer, tmp_len))
+ return -EFAULT;

tmp[tmp_len] = '\0';

@@ -386,7 +386,7 @@ static ssize_t rtl_debugfs_set_write_rfreg(struct file *filp,
if (num != 4) {
rtl_dbg(rtlpriv, COMP_ERR, DBG_DMESG,
"Format is <path> <addr> <mask> <data>\n");
- return count;
+ return -EINVAL;
}

rtl_set_rfreg(hw, path, addr, bitmask, data);
--
2.25.1


2023-03-26 17:36:25

by Larry Finger

[permalink] [raw]
Subject: Re: [PATCH] wireless: rtlwifi: fix incorrect error codes in rtl_debugfs_set_write_rfreg()

On 3/26/23 03:03, Simon Horman wrote:
> On Sun, Mar 26, 2023 at 01:47:51PM +0800, Wei Chen wrote:
>> Dear Simon,
>>
>> Thanks for the advice and review. I have sent the second version of the patch.
>>
>> Besides, rtl_debugfs_set_write_reg also suffers from the incorrect
>> error code problem. I also sent v2 of the corresponding patch. Hope
>> there is no confusion between these two patches.
>
> Thanks. I now see there are two similar but different patches. My bad.

Avoid all such misunderstandings by making a patch set.

Larry