Re: [PATCH] lib/vsprintf.c: remove leftover 'f' and 'F' cases from bstr_printf()

From: Steven Rostedt
Date: Mon Apr 26 2021 - 09:07:58 EST


On Fri, 23 Apr 2021 11:45:29 +0200
Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> wrote:

> Commit 9af7706492f9 ("lib/vsprintf: Remove support for %pF and %pf in
> favour of %pS and %ps") removed support for %pF and %pf, and correctly
> removed the handling of those cases in vbin_printf(). However, the
> corresponding cases in bstr_printf() were left behind.
>
> In the same series, %pf was re-purposed for dealing with
> fwnodes (3bd32d6a2ee6, "lib/vsprintf: Add %pfw conversion specifier
> for printing fwnode names").
>
> So should anyone use %pf with the binary printf routines,
> vbin_printf() would (correctly, as it involves dereferencing the
> pointer) do the string formatting to the u32 array, but bstr_printf()
> would not copy the string from the u32 array, but instead interpret
> the first sizeof(void*) bytes of the formatted string as a pointer -
> which generally won't end well (also, all subsequent get_args would be
> out of sync).
>
> Fixes: 9af7706492f9 ("lib/vsprintf: Remove support for %pF and %pf in favour of %pS and %ps")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
> ---

Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

Thanks!

-- Steve

> lib/vsprintf.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/lib/vsprintf.c b/lib/vsprintf.c
> index 41ddc353ebb8..39ef2e314da5 100644
> --- a/lib/vsprintf.c
> +++ b/lib/vsprintf.c
> @@ -3135,8 +3135,6 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
> switch (*fmt) {
> case 'S':
> case 's':
> - case 'F':
> - case 'f':
> case 'x':
> case 'K':
> case 'e':