From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit 7a4836560a6198d245d5732e26f94898b12eb760 ]
The simple_write_to_buffer() function will succeed if even a single byte is initialized. However, we need to initialize the whole buffer to prevent information leaks. Just use memdup_user().
Fixes: ff974e408334 ("wil6210: debugfs interface to send raw WMI command") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Kalle Valo quic_kvalo@quicinc.com Link: https://lore.kernel.org/r/Ysg14NdKAZF/hcNG@kili Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/ath/wil6210/debugfs.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-)
diff --git a/drivers/net/wireless/ath/wil6210/debugfs.c b/drivers/net/wireless/ath/wil6210/debugfs.c index 2d618f90afa7..58c98e58bccb 100644 --- a/drivers/net/wireless/ath/wil6210/debugfs.c +++ b/drivers/net/wireless/ath/wil6210/debugfs.c @@ -1012,18 +1012,12 @@ static ssize_t wil_write_file_wmi(struct file *file, const char __user *buf, u16 cmdid; int rc, rc1;
- if (cmdlen < 0) + if (cmdlen < 0 || *ppos != 0) return -EINVAL;
- wmi = kmalloc(len, GFP_KERNEL); - if (!wmi) - return -ENOMEM; - - rc = simple_write_to_buffer(wmi, len, ppos, buf, len); - if (rc < 0) { - kfree(wmi); - return rc; - } + wmi = memdup_user(buf, len); + if (IS_ERR(wmi)) + return PTR_ERR(wmi);
cmd = (cmdlen > 0) ? &wmi[1] : NULL; cmdid = le16_to_cpu(wmi->command_id);