diff options
author | Justin Stitt <justinstitt@google.com> | 2023-10-23 19:35:07 +0000 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2023-10-24 17:46:16 -0700 |
commit | 19d1c64b7741d588af56dc70aa21e028737cd73f (patch) | |
tree | 7b8ee9b2e8532a66879f3f7dd9cb5f31878efe12 /drivers/s390 | |
parent | 42c815c545a8b5202a0525c5d2cf1a87c98bdbea (diff) |
s390/ctcm: replace deprecated strncpy with strscpy
strncpy() is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.
We expect chid to be NUL-terminated based on its use with format
strings:
CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s) %s", CTCM_FUNTAIL,
chid, ok ? "OK" : "failed");
Moreover, NUL-padding is not required as it is _only_ used in this one
instance with a format string.
Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.
We can also drop the +1 from chid's declaration as we no longer need to
be cautious about leaving a spot for a NUL-byte. Let's use the more
idiomatic strscpy usage of (dest, src, sizeof(dest)) as this more
closely ties the destination buffer to the length.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Thorsten Winkler <twinkler@linux.ibm.com>
Tested-by: Thorsten Winkler <twinkler@linux.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20231023-strncpy-drivers-s390-net-ctcm_main-c-v1-1-265db6e78165@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/s390')
-rw-r--r-- | drivers/s390/net/ctcm_main.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/s390/net/ctcm_main.c b/drivers/s390/net/ctcm_main.c index 6faf27136024..ac15d7c2b200 100644 --- a/drivers/s390/net/ctcm_main.c +++ b/drivers/s390/net/ctcm_main.c @@ -200,13 +200,13 @@ static void channel_free(struct channel *ch) static void channel_remove(struct channel *ch) { struct channel **c = &channels; - char chid[CTCM_ID_SIZE+1]; + char chid[CTCM_ID_SIZE]; int ok = 0; if (ch == NULL) return; else - strncpy(chid, ch->id, CTCM_ID_SIZE); + strscpy(chid, ch->id, sizeof(chid)); channel_free(ch); while (*c) { |