On Mon, Oct 29, 2018 at 10:54 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > On Wed, Oct 24, 2018 at 1:37 AM Jarkko Sakkinen > <jarkko.sakkinen@xxxxxxxxxxxxxxx> wrote: > > > > On Mon, 22 Oct 2018, ndesaulniers@xxxxxxxxxx wrote: > > > Fixes the warning reported by Clang: > > > security/keys/trusted.c:146:17: warning: passing an object that > > > undergoes default > > > argument promotion to 'va_start' has undefined behavior [-Wvarargs] > > > va_start(argp, h3); > > > ^ > > > security/keys/trusted.c:126:37: note: parameter of type 'unsigned > > > char' is declared here > > > unsigned char *h2, unsigned char h3, ...) > > > ^ > > > Specifically, it seems that both the C90 (4.8.1.1) and C11 (7.16.1.4) > > > standards explicitly call this out as undefined behavior: > > > > > > The parameter parmN is the identifier of the rightmost parameter in > > > the variable parameter list in the function definition (the one just > > > before the ...). If the parameter parmN is declared with ... or with a > > > type that is not compatible with the type that results after > > > application of the default argument promotions, the behavior is > > > undefined. > > > > > > Link: https://github.com/ClangBuiltLinux/linux/issues/41 > > > Link: https://www.eskimo.com/~scs/cclass/int/sx11c.html > > > Suggested-by: David Laight <David.Laight@xxxxxxxxxx> > > > Suggested-by: Denis Kenzior <denkenz@xxxxxxxxx> > > > Suggested-by: James Bottomley <jejb@xxxxxxxxxxxxxxxxxx> > > > Suggested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> > > > Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > > > > Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx> > > > > /Jarkko > > Bumping the maintainers if this isn't already picked up? James, Jarkko, or Mimi, can you please pick this up (and let me know what tree it lands in)? https://lkml.org/lkml/2018/10/23/116 -- Thanks, ~Nick Desaulniers
