[PATCH v2] checkpatch: Check for strcpy and strncpy too

[Kees Cook]

Warn about strcpy(), strncpy(), and strlcpy(). Suggest strscpy() and
include pointers to the open KSPP issues for each, which has further
details and replacement procedures.

Cc: Andy Whitcroft <apw@xxxxxxxxxxxxx>
Cc: Joe Perches <joe@xxxxxxxxxxx>
Cc: Dwaipayan Ray <dwaipayanray1@xxxxxxxxx>
Cc: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230517201349.never.582-kees@xxxxxxxxxx
---
v2: change language to use "Prefer ... over ..." (joe)
v1: https://lore.kernel.org/lkml/20230517201349.never.582-kees@xxxxxxxxxx/
---
 scripts/checkpatch.pl | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index b30114d637c4..30b0b4fdb3bf 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -6997,10 +6997,22 @@ sub process {
 #			}
 #		}
 
+# strcpy uses that should likely be strscpy
+		if ($line =~ /\bstrcpy\s*\(/) {
+			WARN("STRCPY",
+			     "Prefer strscpy over strcpy - see: https://github.com/KSPP/linux/issues/88\n"; . $herecurr);
+		}
+
 # strlcpy uses that should likely be strscpy
 		if ($line =~ /\bstrlcpy\s*\(/) {
 			WARN("STRLCPY",
-			     "Prefer strscpy over strlcpy - see: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw\@mail.gmail.com/\n"; . $herecurr);
+			     "Prefer strscpy over strlcpy - see: https://github.com/KSPP/linux/issues/89\n"; . $herecurr);
+		}
+
+# strncpy uses that should likely be strscpy or strscpy_pad
+		if ($line =~ /\bstrncpy\s*\(/) {
+			WARN("STRNCPY",
+			     "Prefer strscpy, strscpy_pad, or __nonstring over strncpy - see: https://github.com/KSPP/linux/issues/90\n"; . $herecurr);
 		}
 
 # typecasts on min/max could be min_t/max_t
-- 
2.34.1