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