Hi Jurgen, > On 6 Oct 2020, at 09:19, Jürgen Groß <[email protected]> wrote: > > On 06.10.20 09:51, Bertrand Marquis wrote: >>> On 6 Oct 2020, at 05:34, Jürgen Groß <[email protected]> wrote: >>> >>> On 05.10.20 18:02, Bertrand Marquis wrote: >>>> Use memcpy in getBridge to prevent gcc warnings about truncated >>>> strings. We know that we might truncate it, so the gcc warning >>>> here is wrong. >>>> Revert previous change changing buffer sizes as bigger buffers >>>> are not needed. >>>> Signed-off-by: Bertrand Marquis <[email protected]> >>>> --- >>>> tools/libs/stat/xenstat_linux.c | 9 +++++++-- >>>> 1 file changed, 7 insertions(+), 2 deletions(-) >>>> diff --git a/tools/libs/stat/xenstat_linux.c >>>> b/tools/libs/stat/xenstat_linux.c >>>> index d2ee6fda64..1db35c604c 100644 >>>> --- a/tools/libs/stat/xenstat_linux.c >>>> +++ b/tools/libs/stat/xenstat_linux.c >>>> @@ -78,7 +78,12 @@ static void getBridge(char *excludeName, char *result, >>>> size_t resultLen) >>>> sprintf(tmp, "/sys/class/net/%s/bridge", >>>> de->d_name); >>>> if (access(tmp, F_OK) == 0) { >>>> - strncpy(result, de->d_name, resultLen); >>>> + /* >>>> + * Do not use strncpy to prevent >>>> compiler warning with >>>> + * gcc >= 10.0 >>>> + * If de->d_name is longer then >>>> resultLen we truncate it >>>> + */ >>>> + memcpy(result, de->d_name, resultLen - >>>> 1); >>> >>> I think you want min(NAME_MAX, resultLen - 1) for the length. >> true, I will fix that and send a v2. > > Hmm, maybe you should use > > min(strnlen(de->d_name, NAME_MAX), resultLen - 1) > > for the case that de->d_name is near the end of a page, as otherwise > you could try to copy unallocated space. >
Agree, I will do that. Cheers Bertrand
