On 4/13/22 6:21 AM, Nikolay Aleksandrov wrote: >> If a buggy user space application is sending messages with NLM_F_BULK >> set (unintentionally), will it break on newer kernel? I couldn't find >> where the kernel was validating that reserved flags are not used (I >> suspect it doesn't). > > Correct, it doesn't. > >> >> Assuming the above is correct and of interest, maybe just emit a warning >> via extack and drop the goto? Alternatively, we can see if anyone >> complains which might never happen >> > > TBH I prefer to error out on an unsupported flag, but I get the problem. These > weren't validated before and we start checking now. The problem is that we'll > return an extack without an error, but the delete might also remove something. > Hrm.. perhaps we can rephrase the error in that case (since it becomes a warning > in iproute2 terms): > "NLM_F_BULK flag is set but bulk delete operation is not supported" > So it will warn the user it has an unsupported flag. > > WDYT ? > > IMO we should bite the bullet and keep the error though. :) > I agree. The check across the board for BULK flag on any DELETE requests should tell us pretty quick if someone is setting that flag when it should not be.
