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* [PATCH] menuconfig: fix NULL pointer dereference when searching a symbol
@ 2013-05-07  2:40 Li Zefan
  2013-05-07  2:48 ` Libo Chen
                   ` (2 more replies)
  0 siblings, 3 replies; 8+ messages in thread
From: Li Zefan @ 2013-05-07  2:40 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Michal Marek, Weng Meiling, Libo Chen, LKML, linux-kbuild,
	Borislav Petkov

Searching PPC_EFIKA results segmentation fault, and it's because
get_symbol_prop() returns NULL.

In this case CONFIG_PPC_EFIKA is defined in arch/powerpc/platforms/
52xx/Kconfig, so it won't be parsed if ARCH!=PPC, but menuconfig
knows this symbol when it parses sound/soc/fsl/Kconfig:

config SND_MPC52xx_SOC_EFIKA
        tristate "SoC AC97 Audio support for bbplan Efika and STAC9766"
        depends on PPC_EFIKA

This bug was introduced by commit bcdedcc1afd6 ("menuconfig: print more
info for symbol without prompts").

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Li Zefan <lizefan@huawei.com>
---
 scripts/kconfig/menu.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index 826da66..b5c7d90 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -600,14 +600,18 @@ void get_symbol_str(struct gstr *r, struct symbol *sym,
 	}
 	for_all_prompts(sym, prop)
 		get_prompt_str(r, prop, head);
+
 	prop = get_symbol_prop(sym);
-	str_printf(r, _("  Defined at %s:%d\n"), prop->menu->file->name,
-		prop->menu->lineno);
-	if (!expr_is_yes(prop->visible.expr)) {
-		str_append(r, _("  Depends on: "));
-		expr_gstr_print(prop->visible.expr, r);
-		str_append(r, "\n");
+	if (prop) {
+		str_printf(r, _("  Defined at %s:%d\n"), prop->menu->file->name,
+			prop->menu->lineno);
+		if (!expr_is_yes(prop->visible.expr)) {
+			str_append(r, _("  Depends on: "));
+			expr_gstr_print(prop->visible.expr, r);
+			str_append(r, "\n");
+		}
 	}
+
 	hit = false;
 	for_all_properties(sym, prop, P_SELECT) {
 		if (!hit) {
-- 
1.8.0.2

^ permalink raw reply related	[flat|nested] 8+ messages in thread
* [PATCH] menuconfig: fix NULL pointer dereference when searching a symbol
@ 2013-05-07 13:56 Michal Marek
  0 siblings, 0 replies; 8+ messages in thread
From: Michal Marek @ 2013-05-07 13:56 UTC (permalink / raw)
  To: Linus Torvalds
  Cc: Borislav Petkov, Li Zefan, Libo Chen, Yann E. MORIN, linux-kernel

From: Li Zefan <lizefan@huawei.com>

Searching PPC_EFIKA results segmentation fault, and it's because
get_symbol_prop() returns NULL.

In this case CONFIG_PPC_EFIKA is defined in arch/powerpc/platforms/
52xx/Kconfig, so it won't be parsed if ARCH!=PPC, but menuconfig
knows this symbol when it parses sound/soc/fsl/Kconfig:

config SND_MPC52xx_SOC_EFIKA
        tristate "SoC AC97 Audio support for bbplan Efika and STAC9766"
        depends on PPC_EFIKA

This bug was introduced by commit bcdedcc1afd6 ("menuconfig: print more
info for symbol without prompts").

Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Tested-by: Libo Chen <libo.chen@huawei.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
---

This is a fix for a commit that is not in my kconfig branch, therefore
I am sending it directly.

Michal

---
 scripts/kconfig/menu.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index 826da66..b5c7d90 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -600,14 +600,18 @@ void get_symbol_str(struct gstr *r, struct symbol *sym,
 	}
 	for_all_prompts(sym, prop)
 		get_prompt_str(r, prop, head);
+
 	prop = get_symbol_prop(sym);
-	str_printf(r, _("  Defined at %s:%d\n"), prop->menu->file->name,
-		prop->menu->lineno);
-	if (!expr_is_yes(prop->visible.expr)) {
-		str_append(r, _("  Depends on: "));
-		expr_gstr_print(prop->visible.expr, r);
-		str_append(r, "\n");
+	if (prop) {
+		str_printf(r, _("  Defined at %s:%d\n"), prop->menu->file->name,
+			prop->menu->lineno);
+		if (!expr_is_yes(prop->visible.expr)) {
+			str_append(r, _("  Depends on: "));
+			expr_gstr_print(prop->visible.expr, r);
+			str_append(r, "\n");
+		}
 	}
+
 	hit = false;
 	for_all_properties(sym, prop, P_SELECT) {
 		if (!hit) {
-- 
1.8.2.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread
end of thread, other threads:[~2013-05-07 14:13 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-05-07  2:40 [PATCH] menuconfig: fix NULL pointer dereference when searching a symbol Li Zefan
2013-05-07  2:48 ` Libo Chen
2013-05-07 10:44 ` Borislav Petkov
2013-05-07 13:21 ` Yann E. MORIN
2013-05-07 13:47   ` Michal Marek
2013-05-07 14:06     ` Yann E. MORIN
2013-05-07 14:13       ` Michal Marek
  -- strict thread matches above, loose matches on Subject: below --
2013-05-07 13:56 Michal Marek

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