| Message ID | 1606222266-11685-1-git-send-email-tangyouling@loongson.cn |
|---|---|
| State | New |
| Headers | show |
| Series | acpi: Fix use-after-free in acpi_ipmi.c | expand |
On Tue, Nov 24, 2020 at 1:51 PM Youling Tang <tangyouling@loongson.cn> wrote: > > kfree() has been called inside put_device so anther kfree would cause a > use-after-free bug. > > Signed-off-by: Youling Tang <tangyouling@loongson.cn> > --- > drivers/acpi/acpi_ipmi.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c > index 9d6c0fc..72902b6 100644 > --- a/drivers/acpi/acpi_ipmi.c > +++ b/drivers/acpi/acpi_ipmi.c > @@ -130,7 +130,6 @@ ipmi_dev_alloc(int iface, struct device *dev, acpi_handle handle) > ipmi_device, &user); > if (err) { > put_device(dev); > - kfree(ipmi_device); dev doesn't point to the same object in memory as ipmi_device, though, if I'm not mistaken. Please double check that and resend the patch if you are sure that it is correct. > return NULL; > } > ipmi_device->user_interface = user; > @@ -142,7 +141,6 @@ static void ipmi_dev_release(struct acpi_ipmi_device *ipmi_device) > { > ipmi_destroy_user(ipmi_device->user_interface); > put_device(ipmi_device->dev); > - kfree(ipmi_device); > } > > static void ipmi_dev_release_kref(struct kref *kref) > -- > 2.1.0 >
Hi， On 11/25/2020 11:53 PM, Rafael J. Wysocki wrote: > On Tue, Nov 24, 2020 at 1:51 PM Youling Tang <tangyouling@loongson.cn> wrote: >> kfree() has been called inside put_device so anther kfree would cause a >> use-after-free bug. >> >> Signed-off-by: Youling Tang <tangyouling@loongson.cn> >> --- >> drivers/acpi/acpi_ipmi.c | 2 -- >> 1 file changed, 2 deletions(-) >> >> diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c >> index 9d6c0fc..72902b6 100644 >> --- a/drivers/acpi/acpi_ipmi.c >> +++ b/drivers/acpi/acpi_ipmi.c >> @@ -130,7 +130,6 @@ ipmi_dev_alloc(int iface, struct device *dev, acpi_handle handle) >> ipmi_device, &user); >> if (err) { >> put_device(dev); >> - kfree(ipmi_device); > dev doesn't point to the same object in memory as ipmi_device, though, > if I'm not mistaken. > > Please double check that and resend the patch if you are sure that it > is correct. You're right, dev really doesn't point to the same memory object as ipmi_device. I'll send v2 later. Thanks, Youling. >> return NULL; >> } >> ipmi_device->user_interface = user; >> @@ -142,7 +141,6 @@ static void ipmi_dev_release(struct acpi_ipmi_device *ipmi_device) >> { >> ipmi_destroy_user(ipmi_device->user_interface); >> put_device(ipmi_device->dev); >> - kfree(ipmi_device); >> } >> >> static void ipmi_dev_release_kref(struct kref *kref) >> -- >> 2.1.0 >>
diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c index 9d6c0fc..72902b6 100644 --- a/drivers/acpi/acpi_ipmi.c +++ b/drivers/acpi/acpi_ipmi.c @@ -130,7 +130,6 @@ ipmi_dev_alloc(int iface, struct device *dev, acpi_handle handle) ipmi_device, &user); if (err) { put_device(dev); - kfree(ipmi_device); return NULL; } ipmi_device->user_interface = user; @@ -142,7 +141,6 @@ static void ipmi_dev_release(struct acpi_ipmi_device *ipmi_device) { ipmi_destroy_user(ipmi_device->user_interface); put_device(ipmi_device->dev); - kfree(ipmi_device); } static void ipmi_dev_release_kref(struct kref *kref)
kfree() has been called inside put_device so anther kfree would cause a use-after-free bug. Signed-off-by: Youling Tang <tangyouling@loongson.cn> --- drivers/acpi/acpi_ipmi.c | 2 -- 1 file changed, 2 deletions(-)