Messages in this thread | | | Date | Mon, 11 May 2015 16:20:39 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH 1/2] Fix printk() on ERR_PTR() |
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On Sun, 10 May 2015 21:42:15 +0200 Richard Weinberger <richard@nod.at> wrote:
> vbin_printf() checks whether the provided pointer is larger > than -PAGE_SIZE such that it does not explode on ERR_PTR() pointers. > printk() does not. > > Let's add this check also to the printk() code such that > trace_printk() and printk() are consistent again. > > .. > > --- a/lib/vsprintf.c > +++ b/lib/vsprintf.c > @@ -511,7 +511,8 @@ char *string(char *buf, char *end, const char *s, struct printf_spec spec) > { > int len, i; > > - if ((unsigned long)s < PAGE_SIZE) > + if ((unsigned long)s > (unsigned long)-PAGE_SIZE ||
hm, PAGE_SIZE has type ulong, so is the cast needed?
> + (unsigned long)s < PAGE_SIZE)
This would be a place for
if (!within(PAGE_SIZE, (unsigned long)s, -PAGE_SIZE)) s = "(null)";
I'm counting at least five implementations of within(), not all the same.
Maybe. Both the lower and upper bounds will sometimes want inclusive semantics, sometimes exclusive.
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