Commit 3e3533c5 authored Mar 26, 2023 by Wei Chen Committed by Greg Kroah-Hartman May 17, 2023

wifi: rtlwifi: fix incorrect error codes in rtl_debugfs_set_write_reg()



[ 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: 610247f4 ("rtlwifi: Improve debugging by using debugfs")
Signed-off-by: Wei Chen <harperchen1110@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230326054217.93492-1-harperchen1110@gmail.com


Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 03109f18

drivers/net/wireless/realtek/rtlwifi/debug.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -298,8 +298,8 @@ 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';

		@@ -307,7 +307,7 @@ 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: