Commit f5ff432d authored by Azeem Shaikh's avatar Azeem Shaikh Committed by Richard Weinberger
Browse files

um: Remove strlcpy usage 

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89



Signed-off-by: default avatarAzeem Shaikh <azeemshaikh38@gmail.com>
[rw: Massaged subject]
Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
parent 2ccdd1b1

arch/um/include/shared/user.h

+0 −1
Original line number Diff line number Diff line
@@ -50,7 +50,6 @@ static inline int printk(const char *fmt, ...) 
#endif



extern int in_aton(char *str);

extern size_t strlcpy(char *, const char *, size_t);

extern size_t strlcat(char *, const char *, size_t);

extern size_t strscpy(char *, const char *, size_t);

arch/um/os-Linux/umid.c

+3 −3
Original line number Diff line number Diff line
@@ -40,7 +40,7 @@ static int __init make_uml_dir(void) 
				__func__);

			goto err;

		}

		strlcpy(dir, home, sizeof(dir));

		strscpy(dir, home, sizeof(dir));

		uml_dir++;

	}

	strlcat(dir, uml_dir, sizeof(dir));
@@ -243,7 +243,7 @@ int __init set_umid(char *name) 
	if (strlen(name) > UMID_LEN - 1)

		return -E2BIG;



	strlcpy(umid, name, sizeof(umid));

	strscpy(umid, name, sizeof(umid));



	return 0;

}
@@ -262,7 +262,7 @@ static int __init make_umid(void) 
	make_uml_dir();



	if (*umid == '\0') {

		strlcpy(tmp, uml_dir, sizeof(tmp));

		strscpy(tmp, uml_dir, sizeof(tmp));

		strlcat(tmp, "XXXXXX", sizeof(tmp));

		fd = mkstemp(tmp);

		if (fd < 0) {