From: Wei Chen <harperchen1110@xxxxxxxxx>
[ Upstream commit 5dbe1f8eb8c5ac69394400a5b86fd81775e96c43 ]
If there is a failure during copy_from_user or user-provided data buffer is
invalid, rtl_debugfs_set_write_reg 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.
Fixes: 610247f46feb ("rtlwifi: Improve debugging by using debugfs")
Signed-off-by: Wei Chen <harperchen1110@xxxxxxxxx>
Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230326054217.93492-1-harperchen1110@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 deacc7a28d3a7..6a0dfc6d4905e 100644
--- a/drivers/net/wireless/realtek/rtlwifi/debug.c
+++ b/drivers/net/wireless/realtek/rtlwifi/debug.c
@@ -319,8 +319,8 @@ static ssize_t rtl_debugfs_set_write_reg(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';
@@ -328,7 +328,7 @@ static ssize_t rtl_debugfs_set_write_reg(struct file *filp,
num = sscanf(tmp, "%x %x %x", &addr, &val, &len);
if (num != 3)
- return count;
+ return -EINVAL;
switch (len) {
case 1:
--
2.39.2
