kconfig: fix segfault when detecting recursive dependency

Following sample Kconfig generated a segfault:

config FOO
        bool
        select PERF_EVENTS if HAVE_HW_BREAKPOINT

config PERF_EVENTS
        bool

config HAVE_HW_BREAKPOINT
        bool
        depends on PERF_EVENTS

Fix by reverting back to a valid property if there was no
property on the stack of symbols.

The above pattern were seen in sh Kconfig.
A fix for the Kconfig file has been sent to the sh folks.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>

1 files changed, 2 insertions, 0 deletions

diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
index e95718fea355..943712ca6c0a 100644
--- a/scripts/kconfig/symbol.c
+++ b/scripts/kconfig/symbol.c
@@ -937,6 +937,8 @@ static void sym_check_print_recursive(struct symbol *last_sym)
                 sym = stack->sym;
                 next_sym = stack->next ? stack->next->sym : last_sym;
                 prop = stack->prop;
+                if (prop == NULL)
+                        prop = stack->sym->prop;
 
                 /* for choice values find the menu entry (used below) */
                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {