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| author | Jakob Koschel <jakobkoschel@gmail.com> | 2022-03-08 20:18:09 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-15 20:19:44 +0300 |
| commit | 36f4c25ce32ed8a2e6304ebee6246b7f0b3b9a6f (patch) | |
| tree | 6411059e82d97d1e9c4b26a751b48ea314d08d44 /drivers/usb | |
| parent | 6163d4991172b8fff453d2260185d8af971b415e (diff) | |
| download | linux-36f4c25ce32ed8a2e6304ebee6246b7f0b3b9a6f.tar.xz | |
usb: gadget: configfs: remove using list iterator after loop body as a ptr
If the list does not contain the expected element, the value of
list_for_each_entry() iterator will not point to a valid structure.
To avoid type confusion in such case, the list iterator
scope will be limited to list_for_each_entry() loop.
In preparation to limiting scope of a list iterator to the list traversal
loop, use a dedicated pointer to point to the found element [1].
Determining if an element was found is then simply checking if
the pointer is != NULL instead of using the potentially bogus pointer.
Link: https://lore.kernel.org/all/YhdfEIwI4EdtHdym@kroah.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220308171818.384491-18-jakobkoschel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/gadget/configfs.c | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c index d4a678c0806e..1fb837d9271e 100644 --- a/drivers/usb/gadget/configfs.c +++ b/drivers/usb/gadget/configfs.c @@ -418,7 +418,7 @@ static int config_usb_cfg_link( struct usb_function_instance *fi = to_usb_function_instance(usb_func_ci); - struct usb_function_instance *a_fi; + struct usb_function_instance *a_fi = NULL, *iter; struct usb_function *f; int ret; @@ -428,11 +428,13 @@ static int config_usb_cfg_link( * from another gadget or a random directory. * Also a function instance can only be linked once. */ - list_for_each_entry(a_fi, &gi->available_func, cfs_list) { - if (a_fi == fi) - break; + list_for_each_entry(iter, &gi->available_func, cfs_list) { + if (iter != fi) + continue; + a_fi = iter; + break; } - if (a_fi != fi) { + if (!a_fi) { ret = -EINVAL; goto out; } @@ -882,15 +884,17 @@ static int os_desc_link(struct config_item *os_desc_ci, struct gadget_info *gi = os_desc_item_to_gadget_info(os_desc_ci); struct usb_composite_dev *cdev = &gi->cdev; struct config_usb_cfg *c_target = to_config_usb_cfg(usb_cfg_ci); - struct usb_configuration *c; + struct usb_configuration *c = NULL, *iter; int ret; mutex_lock(&gi->lock); - list_for_each_entry(c, &cdev->configs, list) { - if (c == &c_target->c) - break; + list_for_each_entry(iter, &cdev->configs, list) { + if (iter != &c_target->c) + continue; + c = iter; + break; } - if (c != &c_target->c) { + if (!c) { ret = -EINVAL; goto out; } |