Re: [PATCH] fix broken class-based syscall audit

On Mon, May 14, 2007 at 05:51:50PM +0200, Marcus Meissner wrote: > On Mon, May 14, 2007 at 10:46:36AM -0500, Klaus Weidner wrote: > > The sanity check in audit_match_class() is wrong, AUDIT_BITMASK_SIZE is > > 64, providing space for 2048 syscalls in 64 * 32bit integers. The > > comparison only supports 256 syscalls (sizeof __u32 is 4), and silently > > returns "no match" for valid higher-numbered syscalls. [...] > > --- linux-2.6.18.i686/kernel/auditfilter.c.lspp.80 2007-05-11 17:06:08.000000000 -0500 > > +++ linux-2.6.18.i686/kernel/auditfilter.c 2007-05-11 17:09:37.000000000 -0500 > > @@ -306,7 +306,7 @@ > > > > int audit_match_class(int class, unsigned syscall) > > { > > - if (unlikely(syscall >= AUDIT_BITMASK_SIZE * sizeof(__u32))) > > + if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32)) > > return 0; > > if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) > > return 0; > > You likely need to fix audit_register_class() if this is true. I don't see a problem in audit_register_class() - it correctly uses sizeof(__u32) for allocating the memory since that's counted in bytes, only the comparison needs to count bits.