4.4-stable review patch. If anyone has any objections, please let me know.
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From: Jack Pham jackp@codeaurora.org
commit 6cf439e0d37463e42784271179c8a308fd7493c6 upstream.
During _ffs_func_bind(), the received descriptors are evaluated to prepare for binding with the gadget in order to allocate endpoints and optionally set up OS descriptors. However, the high- and super-speed descriptors are only parsed based on whether the gadget_is_dualspeed() and gadget_is_superspeed() calls are true, respectively.
This is a problem in case a userspace program always provides all of the {full,high,super,OS} descriptors when configuring a function. Then, for example if a gadget device is not capable of SuperSpeed, the call to ffs_do_descs() for the SS descriptors is skipped, resulting in an incorrect offset calculation for the vla_ptr when moving on to the OS descriptors that follow. This causes ffs_do_os_descs() to fail as it is now looking at the SS descriptors' offset within the raw_descs buffer instead.
_ffs_func_bind() should evaluate the descriptors unconditionally, so remove the checks for gadget speed.
Fixes: f0175ab51993 ("usb: gadget: f_fs: OS descriptors support") Cc: stable@vger.kernel.org Co-Developed-by: Mayank Rana mrana@codeaurora.org Signed-off-by: Mayank Rana mrana@codeaurora.org Signed-off-by: Jack Pham jackp@codeaurora.org Signed-off-by: Felipe Balbi felipe.balbi@linux.intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/usb/gadget/function/f_fs.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)
--- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -2756,10 +2756,8 @@ static int _ffs_func_bind(struct usb_con struct ffs_data *ffs = func->ffs;
const int full = !!func->ffs->fs_descs_count; - const int high = gadget_is_dualspeed(func->gadget) && - func->ffs->hs_descs_count; - const int super = gadget_is_superspeed(func->gadget) && - func->ffs->ss_descs_count; + const int high = !!func->ffs->hs_descs_count; + const int super = !!func->ffs->ss_descs_count;
int fs_len, hs_len, ss_len, ret, i; struct ffs_ep *eps_ptr;