>This fixes stack smashing I've seen in Okteta. > >The problem is that fd_set by default uses limit (FD_SETSIZE) of 1024, >unless FD_SETSIZE is set before including the <sys/select.h> header. >The Qt4 source code contains some checks, but backtrace from GDB tells >they're not enough. Instead of spending time on looking what's missed, >I've just replaced select(2) with poll(2). Given that code actually >shrunk, and I see no crashes anymore, I think it should go in. > >I suppose this could be a security issue, as you could somehow trigger >stack smashing, but I can't see anything harder than local DoS for now. >But this could be different for some Qt-based apps. There are more >select(2) calls which I'm willing to tweak before, though. This patch >just fixes a problem I faced. > >Remember that Qt4 is EOL, so we don't have to bother about pushing >those patches upstream. On the other side, Qt5 wants same treatment. >Not sure that all platforms Qt5 runs on support poll(2) correctly, >though.
Shocking. (I have been talking about fd_set overflows for almost 15 years, and a few people helped me fix our entire base tree around that time)
