summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAzeem Shaikh <azeemshaikh38@gmail.com>2023-07-03 19:06:41 +0300
committerKees Cook <keescook@chromium.org>2023-07-27 18:51:06 +0300
commit61ce78f29a694772c3b2c5c749589682dbdfec2d (patch)
treeafc9b7a4dc3ab8901917aea3d546cb58af653ecf
parent630fdd592912614a72d00026fdadad72d9ef62eb (diff)
downloadlinux-61ce78f29a694772c3b2c5c749589682dbdfec2d.tar.xz
um: Remove strlcpy declaration
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: Azeem Shaikh <azeemshaikh38@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230703160641.1790935-1-azeemshaikh38@gmail.com Signed-off-by: Kees Cook <keescook@chromium.org>
-rw-r--r--arch/um/include/shared/user.h1
-rw-r--r--arch/um/os-Linux/umid.c6
2 files changed, 3 insertions, 4 deletions
diff --git a/arch/um/include/shared/user.h b/arch/um/include/shared/user.h
index 0347a190429c..981e11d8e025 100644
--- a/arch/um/include/shared/user.h
+++ b/arch/um/include/shared/user.h
@@ -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);
diff --git a/arch/um/os-Linux/umid.c b/arch/um/os-Linux/umid.c
index 7a1abb829930..288c422bfa96 100644
--- a/arch/um/os-Linux/umid.c
+++ b/arch/um/os-Linux/umid.c
@@ -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) {