diff options
| author | Justin Stitt <justinstitt@google.com> | 2023-10-23 22:24:38 +0300 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2023-10-25 16:08:30 +0300 |
| commit | 991a211aa99f468cd291a97b8dcb448ebc77f6c4 (patch) | |
| tree | 0ae08e708a7d890441afafbd0a970dd754535497 /drivers/s390 | |
| parent | e37988bcd1fddb726cf08e4f04a1b8dc4a2f80aa (diff) | |
| download | linux-991a211aa99f468cd291a97b8dcb448ebc77f6c4.tar.xz | |
s390/cio: 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 both `params` and `id` to be NUL-terminated based on their
usage with format strings:
format_node_data(iuparams, iunodeid, &lir->incident_node);
format_node_data(auparams, aunodeid, &lir->attached_node);
switch (lir->iq.class) {
case LIR_IQ_CLASS_DEGRADED:
pr_warn("Link degraded: RS=%02x RSID=%04x IC=%02x "
"IUPARAMS=%s IUNODEID=%s AUPARAMS=%s AUNODEID=%s\n",
sei_area->rs, sei_area->rsid, lir->ic, iuparams,
iunodeid, auparams, aunodeid);
NUL-padding is not required as both `params` and `id` have been memset
to 0:
memset(params, 0, PARAMS_LEN);
memset(id, 0, NODEID_LEN);
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.
Note that there's no overread bugs in the current implementation as the
string literal "n/a" has a size much smaller than PARAMS_LEN or
NODEID_LEN. Nonetheless, let's favor strscpy().
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
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20231023-strncpy-drivers-s390-cio-chsc-c-v1-1-8b76a7b83260@google.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'drivers/s390')
| -rw-r--r-- | drivers/s390/cio/chsc.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c index cc6dc5076ffc..f8b04ce61556 100644 --- a/drivers/s390/cio/chsc.c +++ b/drivers/s390/cio/chsc.c @@ -393,8 +393,8 @@ static void format_node_data(char *params, char *id, struct node_descriptor *nd) memset(id, 0, NODEID_LEN); if (nd->validity != ND_VALIDITY_VALID) { - strncpy(params, "n/a", PARAMS_LEN - 1); - strncpy(id, "n/a", NODEID_LEN - 1); + strscpy(params, "n/a", PARAMS_LEN); + strscpy(id, "n/a", NODEID_LEN); return; } |