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

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

[Rasmus Villemoes]

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@vger.kernel.org
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
---
 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':
-- 
2.29.2

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

[Sakari Ailus]

Hi Rasmus,

On Fri, Apr 23, 2021 at 11:45:29AM +0200, Rasmus Villemoes 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@vger.kernel.org
> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>

Thanks!

Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>

> ---
>  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':
> -- 
> 2.29.2
> 

-- 
Sakari Ailus

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

[Petr Mladek]

On Fri 2021-04-23 11:45:29, Rasmus Villemoes 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@vger.kernel.org
> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>

Great catch!

The patch is pushed in printk/linux.git, branch for-5.13 now.

I did it quickly because the merge window will likely be opened
next week and this should get in.

Best Regards,
Petr

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

[Steven Rostedt]

On Fri, 23 Apr 2021 11:45:29 +0200
Rasmus Villemoes <linux@rasmusvillemoes.dk> 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@vger.kernel.org
> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
> ---

Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

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':