we have to validaddr() and vmemchr() all argv[] elements a second
time when we copy to the new stack to deal with the fact that another
process can come in and modify the memory of the process doing the
exec. so the argv[] strings could have changed and increased in
length. we just make sure the data being copied will fit into the
new stack and error when we would overflow.
also make sure to free the ESEG in case the copy pass errors.
argv[] strings get copied to the new processes stack segment, which
has a maximum size of USTKSIZE, so limit the size of the strings to
that and check early for overflow.
this moves the name validation out of segattach() to syssegattach()
to make sure the segment name cannot be changed by the user while
segattach looks at it.
when executing a script, we did advance argp0 unconditionally
to replace argv[0] with the script name. this fails when
argv[] is empty, then we'd advance argp0 past the nil terminator.
the alternative would be to *not* advance if *argp0 == nil, but that
would require another validaddr() check for a case that is unlikely
to have been anticipated in most programs being invoked as
libc's ARGBEGIN macro assumes argv[0] being non-nil as it also
unconditionally advances the argv pointer.
to keep us sane, we now reject an empty argv[]. on entry, we
verify that argv[] is valid for at least two elements:
- the program name argv[0], has to be non-nil
- the first potential nil terminator in argv[1]
when argv[0] == nil, we throw Ebadarg "bad arg in system call"
this allows members of the -1 group to create new directories in /
without having to fiddle with the fileserver console. this also
makes it consistent to hjfs and cwfs.
this allows members of the -1 group to create new directories in /
without having to fiddle with the fileserver console. this also
makes it consistent to hjfs.
the psaux driver is not used in any kernel configuration and theres
no userspace mouse daemon. i8042auxcmds() is wrong as access
to the user buffer can fault and we are holding an ilocks.
little cleanups in devkbd.
on vmware, loading a new kernel sometimes reboots when
wiggling the mouse. disabling keyboard and mouse on
shutdown fixes the issue.
make sure ps2 mouse is disabled on init, will get re-enabled
in i8042auxenable().
keyboard isnt special anymore, we can just use the devreset
entry point in the device to do the keyboard initialization,
so kbdinit()/kbdenable() are not needed anymore.
the keyboard stops sending interrupts when its fifo gets full,
which can happen on boot when keys get mashed while interrupts
are still disabled. to work arround this, call the keyboard
interrupt handler when kbd.q is starved before blocking.
interpreting octal breaks parsing of decimal numbers with
leading zeros. the manpage listed this in the BUGS section,
so we'r going to fix it as this just causes confusion as
most callers of atoi() do not expect it.
add bootscreenconf(VGAscr *) function, that is called whenever
the framebuffer configuration is changed by devvga. that way, we
can pass the current setting of the framebuffer to the new
kernel when using /dev/reboot.
