diff options
| author | Linyu Yuan <quic_linyyuan@quicinc.com> | 2022-06-10 15:17:58 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-06-22 15:22:04 +0300 |
| commit | 4baa493636b6ade2beb2698151f94de4c4cddbb8 (patch) | |
| tree | 56379fc60dae7c9b2c8d2a00d40ae25af9bb9ef6 | |
| parent | 20ac0adece7b18dd79467223b35e718223ccbf3d (diff) | |
| download | linux-4baa493636b6ade2beb2698151f94de4c4cddbb8.tar.xz | |
usb: gadget: f_fs: change ep->ep safe in ffs_epfile_io()
commit 0698f0209d8032e8869525aeb68f65ee7fde12ad upstream.
In ffs_epfile_io(), when read/write data in blocking mode, it will wait
the completion in interruptible mode, if task receive a signal, it will
terminate the wait, at same time, if function unbind occurs,
ffs_func_unbind() will kfree all eps, ffs_epfile_io() still try to
dequeue request by dereferencing ep which may become invalid.
Fix it by add ep spinlock and will not dereference ep if it is not valid.
Cc: <stable@vger.kernel.org> # 5.15
Reported-by: Michael Wu <michael@allwinnertech.com>
Tested-by: Michael Wu <michael@allwinnertech.com>
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Link: https://lore.kernel.org/r/1654863478-26228-3-git-send-email-quic_linyyuan@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/gadget/function/f_fs.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 26844760b509..adc44a2685b5 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -1080,6 +1080,11 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data) spin_unlock_irq(&epfile->ffs->eps_lock); if (wait_for_completion_interruptible(&io_data->done)) { + spin_lock_irq(&epfile->ffs->eps_lock); + if (epfile->ep != ep) { + ret = -ESHUTDOWN; + goto error_lock; + } /* * To avoid race condition with ffs_epfile_io_complete, * dequeue the request first then check @@ -1087,6 +1092,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data) * condition with req->complete callback. */ usb_ep_dequeue(ep->ep, req); + spin_unlock_irq(&epfile->ffs->eps_lock); wait_for_completion(&io_data->done); interrupted = io_data->status < 0; } |