From: Wei Yongjun Date: Sun, 6 Jun 2021 15:37:40 +0000 (+0530) Subject: bus: mhi: pci_generic: Fix possible use-after-free in mhi_pci_remove() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=0b67808ade8893a1b3608ddd74fac7854786c919;p=linux.git bus: mhi: pci_generic: Fix possible use-after-free in mhi_pci_remove() This driver's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself. Link: https://lore.kernel.org/r/20210413160318.2003699-1-weiyongjun1@huawei.com Fixes: 8562d4fe34a3 ("mhi: pci_generic: Add health-check") Cc: stable Reported-by: Hulk Robot Reviewed-by: Hemant kumar Reviewed-by: Manivannan Sadhasivam Reviewed-by: Loic Poulain Signed-off-by: Wei Yongjun Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20210606153741.20725-3-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c index 8c7f6576e421d..0a6619ad292cd 100644 --- a/drivers/bus/mhi/pci_generic.c +++ b/drivers/bus/mhi/pci_generic.c @@ -708,7 +708,7 @@ static void mhi_pci_remove(struct pci_dev *pdev) struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; - del_timer(&mhi_pdev->health_check_timer); + del_timer_sync(&mhi_pdev->health_check_timer); cancel_work_sync(&mhi_pdev->recovery_work); if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) {