pinctrl: s32cc: Avoid possible string truncation

[ Upstream commit 08e8734d877a9a0fb8af1254a4ce58734fbef296 ]

With "W=1" and "-Wformat-truncation" build options, the kernel test robot
found a possible string truncation warning in pinctrl-s32cc.c, which uses
an 8-byte char array to hold a memory region name "map%u". Since the
maximum number of digits that a u32 value can present is 10, and the "map"
string occupies 3 bytes with a termination '\0', which means the rest 4
bytes cannot fully present the integer "X" that exceeds 4 digits.

Here we check if the number >= 10000, which is the lowest value that
contains more than 4 digits.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311030159.iyUGjNGF-lkp@intel.com/
Signed-off-by: Chester Lin <clin@suse.com>
Link: https://lore.kernel.org/r/20231107141044.24058-1-clin@suse.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/pinctrl/nxp/pinctrl-s32cc.c b/drivers/pinctrl/nxp/pinctrl-s32cc.c
index 7daff9f..f0cad2c 100644 (file)
--- a/drivers/pinctrl/nxp/pinctrl-s32cc.c
+++ b/drivers/pinctrl/nxp/pinctrl-s32cc.c
@@ -843,8 +843,8 @@ static int s32_pinctrl_probe_dt(struct platform_device *pdev,
        if (!np)
                return -ENODEV;
 
-       if (mem_regions == 0) {
-               dev_err(&pdev->dev, "mem_regions is 0\n");
+       if (mem_regions == 0 || mem_regions >= 10000) {
+               dev_err(&pdev->dev, "mem_regions is invalid: %u\n", mem_regions);
                return -EINVAL;
        }