On Tue, Apr 17, 2012 at 6:51 AM, Willy Tarreau <w@xxxxxx> wrote: > Hi Michael, > > On Tue, Apr 17, 2012 at 10:44:15PM +1200, Michael Kerrisk wrote: > (...) >> The accompanying patch changes unix_mkname() to ensure that a terminating >> null byte is always located within the first 108 bytes of sun_path. >> It does change the ABI for the former case where a pathname ran to 108 >> bytes without a null terminator: for that case, the call now fails with >> the error -EINVAL. What are people's thoughts on applying this? > > My personal opinion is that (as you said), the risk of breaking existing > apps is already fairly low, but we must not deliberately break existing > apps. Eventhough there are currently a log, this is exactly what sysctls > are made for. I would personally like to have a default limit to 107 chars > + one zero, with a sysctl option to revert to current behaviour if ever it > broke an application. In my opinion it's exactly comparable to the risk of > breaking apps with mmap_min_addr : very low risk but must be covered by a > workaround (sysctl). To further the opinion that the risk is low: The Open Solaris SUN_LEN macro uses strlen to compute the length. The glibc SUN_LEN macro uses strlen to compute the length. The Mac OS X libc SUN_LEN macro uses strlen to compute the length. The linux man-pages project sets the user expectation that it is a `null-terminated string' (circular argument). I see every expectation from userspace/glibc that it should be 107 chars + '\0'. Cheers, Carlos. -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
