On 2024/8/1 18:37, Leon Romanovsky wrote: > On Thu, Aug 01, 2024 at 03:44:15PM +0800, Junxian Huang wrote: >> Currently cancel_work_sync() is not called when srpt_refresh_port() >> failed in srpt_add_one(). There is a probability that sdev has been >> freed while the previously initiated sport->work is still running, >> leading to a UAF as the log below: >> >> [ T880] ib_srpt MAD registration failed for hns_1-1. >> [ T880] ib_srpt srpt_add_one(hns_1) failed. >> [ T376] Unable to handle kernel paging request at virtual address 0000000000010008 >> ... >> [ T376] Workqueue: events srpt_refresh_port_work [ib_srpt] >> ... >> [ T376] Call trace: >> [ T376] srpt_refresh_port+0x94/0x264 [ib_srpt] >> [ T376] srpt_refresh_port_work+0x1c/0x2c [ib_srpt] >> [ T376] process_one_work+0x1d8/0x4cc >> [ T376] worker_thread+0x158/0x410 >> [ T376] kthread+0x108/0x13c >> [ T376] ret_from_fork+0x10/0x18 >> >> Add cancel_work_sync() to the exception branch to fix this UAF. >> >> Fixes: a42d985bd5b2 ("ib_srpt: Initial SRP Target merge for v3.3-rc1") >> Signed-off-by: Junxian Huang <huangjunxian6@xxxxxxxxxxxxx> >> --- >> drivers/infiniband/ulp/srpt/ib_srpt.c | 5 +++-- >> 1 file changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c >> index 9632afbd727b..244e5c115bf7 100644 >> --- a/drivers/infiniband/ulp/srpt/ib_srpt.c >> +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c >> @@ -3148,8 +3148,8 @@ static int srpt_add_one(struct ib_device *device) >> { >> struct srpt_device *sdev; >> struct srpt_port *sport; >> + u32 i, j; >> int ret; >> - u32 i; >> >> pr_debug("device = %p\n", device); >> >> @@ -3226,7 +3226,6 @@ static int srpt_add_one(struct ib_device *device) >> if (ret) { >> pr_err("MAD registration failed for %s-%d.\n", >> dev_name(&sdev->device->dev), i); >> - i--; >> goto err_port; >> } >> } >> @@ -3241,6 +3240,8 @@ static int srpt_add_one(struct ib_device *device) >> return 0; >> >> err_port: >> + for (j = i, i--; j > 0; j--)a >> + cancel_work_sync(&sdev->port[j - 1].work); > > There is no need in extra variable, the following code will do the same: > > while (i--) > cancel_work_sync(&sdev->port[i].work); > >> srpt_unregister_mad_agent(sdev, i); i is also used here. Junxian >> err_cm: >> if (sdev->cm_id) >> -- >> 2.33.0 >> >