diff options
author | Azeem Shaikh <azeemshaikh38@gmail.com> | 2023-08-31 14:01:04 +0000 |
---|---|---|
committer | Kees Cook <keescook@chromium.org> | 2023-09-22 09:50:56 -0700 |
commit | 6cd59324c69a8d30956c70a870dcd0cb14977914 (patch) | |
tree | c36371f0246a436f8495eaf8feae2a638327db29 /lib | |
parent | 8ebab155ea18a6d6c47b17287a0ab4633334f6eb (diff) |
kobject: Replace strlcpy with strscpy
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().
Direct replacement is safe here since return value of -errno
is used to check for truncation instead of sizeof(dest).
[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/20230831140104.207019-1-azeemshaikh38@gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/kobject_uevent.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index 7c44b7ae4c5c..fb9a2f06dd1e 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -254,10 +254,10 @@ static int init_uevent_argv(struct kobj_uevent_env *env, const char *subsystem) int buffer_size = sizeof(env->buf) - env->buflen; int len; - len = strlcpy(&env->buf[env->buflen], subsystem, buffer_size); - if (len >= buffer_size) { - pr_warn("init_uevent_argv: buffer size of %d too small, needed %d\n", - buffer_size, len); + len = strscpy(&env->buf[env->buflen], subsystem, buffer_size); + if (len < 0) { + pr_warn("%s: insufficient buffer space (%u left) for %s\n", + __func__, buffer_size, subsystem); return -ENOMEM; } |