In __iodyn_find_io_region(), pcmcia_make_resource() is assigned to
res and used in pci_bus_alloc_resource(). There is a dereference of res
in pci_bus_alloc_resource(), which could lead to a NULL pointer
dereference on failure of pcmcia_make_resource().
Fix this bug by adding a check of res.
Found by code review, complie tested only.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 49b1153adfe1 ("pcmcia: move all pcmcia_resource_ops providers into one module")
Signed-off-by: Ma Ke <make24@xxxxxxxxxxx>
---
drivers/pcmcia/rsrc_iodyn.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/pcmcia/rsrc_iodyn.c b/drivers/pcmcia/rsrc_iodyn.c
index b04b16496b0c..2677b577c1f8 100644
--- a/drivers/pcmcia/rsrc_iodyn.c
+++ b/drivers/pcmcia/rsrc_iodyn.c
@@ -62,6 +62,9 @@ static struct resource *__iodyn_find_io_region(struct pcmcia_socket *s,
unsigned long min = base;
int ret;
+ if (!res)
+ return NULL;
+
data.mask = align - 1;
data.offset = base & data.mask;
--
2.25.1
