> Ok, this gives us a definite proposal, which I finally like:
>
> * to exclude sys_tee:
>
> bitmask = 0;
> set_bit(__NR_tee, bitmask);
> ptrace(PTRACE_SET_NOTRACE, bitmask);
>
> * to trace only sys_tee:
>
> bitmask = 0;
> set_bit(__NR_tee, bitmask);
> ptrace(PTRACE_SET_TRACEONLY, bitmask);
>
> Semantics:
>
> in both cases, the mask is first zero-extended to the right (for syscalls not
> known to userspace), bits for syscall not known to the kernel are checked and
> the call fails if any of them is 1, and in the failure case E2BIG or
> EOVERFLOW is returned (I want to avoid EINVAL and ENOSYS to avoid confusion)
> and the part of the mask known to the kernel is 0-ed.
>
> In case of success, for NOTRACE (which was DEFAULT_TRACE) the mask is reversed
> before copying in the kernel syscall mask, for TRACEONLY it's copied there
> directly.
IMHO this is way too complicated. Introducing a ptrace call that returns
the number of syscalls and forcing user space to pass a complete bitmask
is much easier. Also the semantics are much easier to understand.
In addition your proposal would already introduce a rather complicated
interface to figure out how many syscalls the kernel has. I'm sure this
will be (mis)used sooner or later.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
