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@vger.kernel.org Fixes: 49b1153adfe1 ("pcmcia: move all pcmcia_resource_ops providers into one module") Signed-off-by: Ma Ke make24@iscas.ac.cn --- 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;