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| author | Jakob Koschel <jakobkoschel@gmail.com> | 2022-03-08 18:18:13 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-15 18:19:44 +0100 |
| commit | eb6dc99ea2364a149ad61dd04637ea3b20434304 (patch) | |
| tree | 78bde72af676e815d5ac387f8c084efd15b878f0 /drivers/usb | |
| parent | 418947745c8e0e3835bd64a4123837d05ef808cd (diff) | |
| download | linux-eb6dc99ea2364a149ad61dd04637ea3b20434304.tar.bz2 | |
usb: gadget: composite: remove check of list iterator against head past the loop body
When list_for_each_entry() completes the iteration over the whole list
without breaking the loop, the iterator value will be a bogus pointer
computed based on the head element.
While it is safe to use the pointer to determine if it was computed
based on the head element, either with list_entry_is_head() or
&pos->member == head, using the iterator variable after the loop should
be avoided.
In preparation to limiting the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element [1].
Link: https://lore.kernel.org/all/YhdfEIwI4EdtHdym@kroah.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220308171818.384491-22-jakobkoschel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/gadget/composite.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index 9315313108c9..4f7e789c3e07 100644 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -1690,6 +1690,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) u16 w_value = le16_to_cpu(ctrl->wValue); u16 w_length = le16_to_cpu(ctrl->wLength); struct usb_function *f = NULL; + struct usb_function *iter; u8 endp; if (w_length > USB_COMP_EP0_BUFSIZ) { @@ -2046,12 +2047,12 @@ unknown: if (!cdev->config) break; endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f); - list_for_each_entry(f, &cdev->config->functions, list) { - if (test_bit(endp, f->endpoints)) + list_for_each_entry(iter, &cdev->config->functions, list) { + if (test_bit(endp, iter->endpoints)) { + f = iter; break; + } } - if (&f->list == &cdev->config->functions) - f = NULL; break; } try_fun_setup: |