In the nokia gadget some USB functions (obex 1 and 2, phonet) are optional.
If at the start of nokia_bind_config e.g. fi_phonet is an error pointer,
which can happen because we don't fail the bind process if
usb_get_function_instance() fails for fi_phonet, then f_phonet is NULL, and
phonet_stat = usb_add_function(c, f_phonet);
is never called and phonet_stat remains 0.
If, in these circumstances, we hit the err_conf label then !phonet_stat
evaluates to true and we try usb_remove_function() with its second
parameter being f_phonet which is NULL and it causes NULL pointer
dereference.
This patch changes the initial values of (obex1|obex2|phonet)_stat to a
nonzero value so that if the err_conf label is hit while the respective
functions have not been acquired the usb_remove_function() is not called
for those functions.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@xxxxxxxxxxx>
---
v1..v2:
- obex1/obex2/phonet_stat now initialized to -ENODEV instead of -1
drivers/usb/gadget/nokia.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/gadget/nokia.c b/drivers/usb/gadget/nokia.c
index 0a8099a..9598ed7 100644
--- a/drivers/usb/gadget/nokia.c
+++ b/drivers/usb/gadget/nokia.c
@@ -126,9 +126,9 @@ static int __init nokia_bind_config(struct usb_configuration *c)
struct usb_function *f_ecm;
struct usb_function *f_obex2 = NULL;
int status = 0;
- int obex1_stat = 0;
- int obex2_stat = 0;
- int phonet_stat = 0;
+ int obex1_stat = -ENODEV;
+ int obex2_stat = -ENODEV;
+ int phonet_stat = -ENODEV;
if (!IS_ERR(fi_phonet)) {
f_phonet = usb_get_function(fi_phonet);
--
1.7.0.4
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