Re: [Qemu-devel] [PATCH] hmp: avoid redundant null termination of buffer

[P J P <ppandit@redhat.com>]

+-- On Fri, 8 Jan 2016, Wolfgang Bumiller wrote --+
| On Fri, Jan 08, 2016 at 07:29:31PM +0530, P J P wrote:
| >   + if (!strncmp(keyname_buf, "<-", 2))
| > and remove the 'keyname_len' altogether.
| 
| This wouldn't catch '<' without '-'. (`sendkey <`)
| Also, strncmp with a length of 1 (in the original) seems weird.

  Ah, true.
 
| keyname_len is not useless and perhaps it would be best to just do an
| early error check there as I do below.
| 
| Alternatively the if() can simply happen after pstrcpy() as a cut-off
| error should be good enough anyway.
| 
| @@ -1749,6 +1749,9 @@ void hmp_sendkey(Monitor *mon, const QDict *qdict)
|      while (1) {
|          separator = strchr(keys, '-');
|          keyname_len = separator ? separator - keys : strlen(keys);
| +        if (keyname_len >= sizeof(keyname_buf))
| +            goto err_out;
| +
|          pstrcpy(keyname_buf, sizeof(keyname_buf), keys);

  Yes, this looks good. With that, maybe 'keyname_len' could be sent to 
pstrcpy() above, instead of sizeof(keyname_buf)? If so, then the subsequent if 
could say: if (!strcmp(keyname_buf, "<")).

--
 - P J P
47AF CE69 3A90 54AA 9045 1053 DD13 3D32 FE5B 041F