| Message ID | 77f0dc4f3966591d1f0cffb614a94085f8895a85.1627560174.git.christophe.jaillet@wanadoo.fr (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e9c5b0b53ccca81dd0a35c62309e243a57c7959d |
| Headers | show |
| Series | dmaengine: idxd: Fix a possible NULL pointer dereference | expand |
On 7/29/2021 5:04 AM, Christophe JAILLET wrote: > 'device_driver_attach()' dereferences its first argument (i.e. 'alt_drv') > so it must not be NULL. > Simplify the error handling logic about NULL 'alt_drv' in order to be > more robust and future-proof. > > Fixes: 568b2126466f ("dmaengine: idxd: fix uninit var for alt_drv") > Fixes: 6e7f3ee97bbe ("dmaengine: idxd: move dsa_drv support to compatible mode") > > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Thanks for the cleanup. Acked-by: Dave Jiang <dave.jiang@intel.com> > --- > drivers/dma/idxd/compat.c | 15 ++++----------- > 1 file changed, 4 insertions(+), 11 deletions(-) > > diff --git a/drivers/dma/idxd/compat.c b/drivers/dma/idxd/compat.c > index d7616c240dcd..3df21615f888 100644 > --- a/drivers/dma/idxd/compat.c > +++ b/drivers/dma/idxd/compat.c > @@ -45,23 +45,16 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t cou > idxd_dev = confdev_to_idxd_dev(dev); > if (is_idxd_dev(idxd_dev)) { > alt_drv = driver_find("idxd", bus); > - if (!alt_drv) > - return -ENODEV; > } else if (is_idxd_wq_dev(idxd_dev)) { > struct idxd_wq *wq = confdev_to_wq(dev); > > - if (is_idxd_wq_kernel(wq)) { > + if (is_idxd_wq_kernel(wq)) > alt_drv = driver_find("dmaengine", bus); > - if (!alt_drv) > - return -ENODEV; > - } else if (is_idxd_wq_user(wq)) { > + else if (is_idxd_wq_user(wq)) > alt_drv = driver_find("user", bus); > - if (!alt_drv) > - return -ENODEV; > - } else { > - return -ENODEV; > - } > } > + if (!alt_drv) > + return -ENODEV; > > rc = device_driver_attach(alt_drv, dev); > if (rc < 0)
On 29-07-21, 14:04, Christophe JAILLET wrote: > 'device_driver_attach()' dereferences its first argument (i.e. 'alt_drv') > so it must not be NULL. > Simplify the error handling logic about NULL 'alt_drv' in order to be > more robust and future-proof. Applied, thanks
diff --git a/drivers/dma/idxd/compat.c b/drivers/dma/idxd/compat.c index d7616c240dcd..3df21615f888 100644 --- a/drivers/dma/idxd/compat.c +++ b/drivers/dma/idxd/compat.c @@ -45,23 +45,16 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t cou idxd_dev = confdev_to_idxd_dev(dev); if (is_idxd_dev(idxd_dev)) { alt_drv = driver_find("idxd", bus); - if (!alt_drv) - return -ENODEV; } else if (is_idxd_wq_dev(idxd_dev)) { struct idxd_wq *wq = confdev_to_wq(dev); - if (is_idxd_wq_kernel(wq)) { + if (is_idxd_wq_kernel(wq)) alt_drv = driver_find("dmaengine", bus); - if (!alt_drv) - return -ENODEV; - } else if (is_idxd_wq_user(wq)) { + else if (is_idxd_wq_user(wq)) alt_drv = driver_find("user", bus); - if (!alt_drv) - return -ENODEV; - } else { - return -ENODEV; - } } + if (!alt_drv) + return -ENODEV; rc = device_driver_attach(alt_drv, dev); if (rc < 0)
'device_driver_attach()' dereferences its first argument (i.e. 'alt_drv') so it must not be NULL. Simplify the error handling logic about NULL 'alt_drv' in order to be more robust and future-proof. Fixes: 568b2126466f ("dmaengine: idxd: fix uninit var for alt_drv") Fixes: 6e7f3ee97bbe ("dmaengine: idxd: move dsa_drv support to compatible mode") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> --- drivers/dma/idxd/compat.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-)