From 81386ed40590bf746849ce1a1d3a2edd869bad84 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Mon, 27 Sep 2021 14:22:01 +0300 Subject: [PATCH] scripts: ensure the cocci script for miiphy_register does not leave NULL-unterminated strings strncpy() simply bails out when copying a source string whose size exceeds the destination string size, potentially leaving the destination string unterminated. One possible way to address is to pass MDIO_NAME_LEN - 1 and a previously zero-initialized destination string, but this is more difficult to maintain. The chosen alternative is to use strlcpy(), which properly limits the copy len in the (srclen >= size) case to "size - 1", and which is also more efficient than the strncpy() byte-by-byte implementation by using memcpy. The destination string returned by strlcpy() is always NULL terminated. Signed-off-by: Vladimir Oltean --- scripts/coccinelle/net/mdio_register.cocci | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/coccinelle/net/mdio_register.cocci b/scripts/coccinelle/net/mdio_register.cocci index 100f102936..31a40360f9 100644 --- a/scripts/coccinelle/net/mdio_register.cocci +++ b/scripts/coccinelle/net/mdio_register.cocci @@ -16,7 +16,7 @@ identifier readfunc, writefunc; - miiphy_register(devname, readfunc, writefunc); + struct mii_dev *mdiodev = mdio_alloc(); + if (!mdiodev) return -ENOMEM; -+ strncpy(mdiodev->name, devname, MDIO_NAME_LEN); ++ strlcpy(mdiodev->name, devname, MDIO_NAME_LEN); + mdiodev->read = readfunc; + mdiodev->write = writefunc; + -- 2.39.5