This makes sure format strings cannot leak into printk (the string has
already been correctly processed for format arguments).
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It is possible to configure a kernel which has xmon enabled, but has no
udbg backend to provide IO. This can make xmon rather confusing, as it
produces no output, blocks for two seconds, and then returns.
As a last resort we can instead try to printk(), which may deadlock or
otherwise crash, but tries quite hard not to.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The routines in start.c are only ever called from nonstdio.c, so if we
move them in there they can become static which is nice.
I suspect the idea behind the separation was that start.c could be
replaced in order to build xmon in userland. If anyone still cares about
doing that we could handle that with an ifdef or two.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
xmon_getchar() is only called from within nonstdio.c, so make it static.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It looks like xmon_expect() was used for doing xmon over a modem (!?),
that code was dropped in 2005 in commit 51d3082 "Unify udbg (#2)".
Once xmon_expect() is gone xmon_read_poll() is unused, drop it too.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In some configuration, xmon help string is larger than xmon_printf
buffer. We need not to use printf. This patch adds xmon_puts and
change to use it to show help string.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This factors out the common bits of arch/powerpc/xmon/start_*.c into
a new nonstdio.c, and removes some stuff that was supposed to make
xmon's I/O routines somewhat stdio-like but was never used.
It also makes the parsing of the xmon= command line option common,
so that ppc32 can now use xmon={off,on,early} also.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Kees Cook
Michael Ellerman
Ishizaki Kou
Paul Mackerras