Re: [PATCH V2] net: ethernet: myricom: myri10ge: myri10ge.c: Cleaning up missing null-terminate after strncpy call

2014-08-13 19:06 GMT+02:00 Jiri Pirko [off-list ref]:

Mon, Aug 11, 2014 at 09:18:16PM CEST, rickard_strandqvist@spectrumdigital.se wrote:

quoted

Added a guaranteed null-terminate after call to strncpy.

Signed-off-by: Rickard Strandqvist <redacted>
---
drivers/net/ethernet/myricom/myri10ge/myri10ge.c |    1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
index f3d5d79..69c26f0 100644
--- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
+++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c

@@ -574,6 +574,7 @@ myri10ge_validate_firmware(struct myri10ge_priv *mgp,

      /* save firmware version for ethtool */
      strncpy(mgp->fw_version, hdr->version, sizeof(mgp->fw_version));
+      mgp->fw_version[sizeof(mgp->fw_version) - 1] = '\0';

        Why not to use strlcpy?

quoted

      sscanf(mgp->fw_version, "%d.%d.%d", &mgp->fw_ver_major,
             &mgp->fw_ver_minor, &mgp->fw_ver_tiny);
--
1.7.10.4

Hi

Sure, strlcpy is preferable in many ways if we only can guarantee that
it is safe.
I have seldom received so much criticism when I start switching to
strlcpy, although much of it was justified :)
Even Linus was getting into the debate.  See more:

https://plus.google.com/111049168280159033135/posts/1amLbuhWbh5


I change to strlcpy only when I'm sure it will not cause any other problems.
But if you or anyone else can guarantee that in this case, so I'd make
a new patch with strlcpy.


Kind regards

Rickard Strandqvist