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 chinfo.name to be NUL-terminated based on its usage with
strncmp():
rpmsg_core.c:
389: if (strncmp(chinfo->name, rpdev->id.name, RPMSG_NAME_SIZE))
Moreover, NUL-padding is not required as chinfo has stack default
initialized all fields to zero:
rpmsg_core.c:
539: struct rpmsg_channel_info chinfo = {};
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.
Also, favor the more idiomatic strscpy() usage of:
(dest, src, sizeof(dest)).
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@xxxxxxxxxxxxxxx
Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx>
Similar-to: https://lore.kernel.org/all/20231018-strncpy-drivers-net-wwan-rpmsg_wwan_ctrl-c-v1-1-4e343270373a@xxxxxxxxxx/
---
Note: build-tested only.
Found with: $ rg "strncpy\("
---
drivers/rpmsg/rpmsg_core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index 32b550c91d9f..8abc7d022ff7 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -545,7 +545,7 @@ static int rpmsg_dev_probe(struct device *dev)
goto out;
if (rpdrv->callback) {
- strncpy(chinfo.name, rpdev->id.name, RPMSG_NAME_SIZE);
+ strscpy(chinfo.name, rpdev->id.name, sizeof(chinfo.name));
chinfo.src = rpdev->src;
chinfo.dst = RPMSG_ADDR_ANY;
---
base-commit: bb55d7f7f7445abcc8db50e6a65d4315e79f75c7
change-id: 20231020-strncpy-drivers-rpmsg-rpmsg_core-c-e32ea739a375
Best regards,
--
Justin Stitt <justinstitt@xxxxxxxxxx>
