On Fri, 14 Nov 2025 08:43:46 -0500 Steven Rostedt <[email protected]> wrote:
> On Fri, 14 Nov 2025 13:27:47 +0100 > Thorsten Blum <[email protected]> wrote: > > > Add the __counted_by() compiler attribute to the flexible array member > > 'entries' to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and > > CONFIG_FORTIFY_SOURCE. > > > > Signed-off-by: Thorsten Blum <[email protected]> > > --- > > include/linux/unwind_deferred_types.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/include/linux/unwind_deferred_types.h > > b/include/linux/unwind_deferred_types.h > > index 33b62ac25c86..d4b67f0116f3 100644 > > --- a/include/linux/unwind_deferred_types.h > > +++ b/include/linux/unwind_deferred_types.h > > @@ -5,7 +5,7 @@ > > struct unwind_cache { > > unsigned long unwind_completed; > > unsigned int nr_entries; > > - unsigned long entries[]; > > + unsigned long entries[] __counted_by(nr_entries); > > }; > > > > /* > > Wrong! > > I need to add a comment here that entries is not bound by nr_entries. > > https://lore.kernel.org/all/[email protected]/ > > Maybe this?: > > diff --git a/include/linux/unwind_deferred_types.h > b/include/linux/unwind_deferred_types.h > index 33b62ac25c86..d05409bb14fa 100644 > --- a/include/linux/unwind_deferred_types.h > +++ b/include/linux/unwind_deferred_types.h > @@ -5,7 +5,7 @@ > struct unwind_cache { > unsigned long unwind_completed; Does that need to be 'long' - 'int' would fit in the padding on 64bit. > unsigned int nr_entries; > - unsigned long entries[]; > + unsigned long entries[]; /* Fixed size, not bound by > nr_entries */ > }; Perhaps it should be: unsigned long entries[ /* MAX_UNWIND_ENTRIES */ ]; David > > /* > > > > -- Steve >
