* [PATCH] uverbs: prevent potential underflow
@ 2019-10-05 5:23 Dan Carpenter
2019-10-08 19:44 ` Jason Gunthorpe
0 siblings, 1 reply; 5+ messages in thread
From: Dan Carpenter @ 2019-10-05 5:23 UTC (permalink / raw)
To: Doug Ledford, Potnuri Bharat Teja, Matan Barak
Cc: Jason Gunthorpe, Leon Romanovsky, Shamir Rabinovitch,
Matthew Wilcox, Michael Guralnik, linux-rdma, linux-kernel,
kernel-janitors
The issue is in drivers/infiniband/core/uverbs_std_types_cq.c in the
UVERBS_HANDLER(UVERBS_METHOD_CQ_CREATE) function. We check that:
if (attr.comp_vector >= attrs->ufile->device->num_comp_vectors) {
But we don't check that "attr.comp_vector" whether negative. It
could potentially lead to an array underflow. My concern would be where
cq->vector is used in the create_cq() function from the cxgb4 driver.
Fixes: 9ee79fce3642 ("IB/core: Add completion queue (cq) object actions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
drivers/infiniband/core/uverbs.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h
index 1e5aeb39f774..63f7f7db5902 100644
--- a/drivers/infiniband/core/uverbs.h
+++ b/drivers/infiniband/core/uverbs.h
@@ -98,7 +98,7 @@ ib_uverbs_init_udata_buf_or_null(struct ib_udata *udata,
struct ib_uverbs_device {
atomic_t refcount;
- int num_comp_vectors;
+ u32 num_comp_vectors;
struct completion comp;
struct device dev;
/* First group for device attributes, NULL terminated array */
--
2.20.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH] uverbs: prevent potential underflow
2019-10-05 5:23 [PATCH] uverbs: prevent potential underflow Dan Carpenter
@ 2019-10-08 19:44 ` Jason Gunthorpe
2019-10-09 7:35 ` Dan Carpenter
2019-10-11 13:34 ` [PATCH v2] " Dan Carpenter
0 siblings, 2 replies; 5+ messages in thread
From: Jason Gunthorpe @ 2019-10-08 19:44 UTC (permalink / raw)
To: Dan Carpenter
Cc: Doug Ledford, Potnuri Bharat Teja, Matan Barak, Leon Romanovsky,
Shamir Rabinovitch, Matthew Wilcox, Michael Guralnik, linux-rdma,
linux-kernel, kernel-janitors
On Sat, Oct 05, 2019 at 08:23:37AM +0300, Dan Carpenter wrote:
> The issue is in drivers/infiniband/core/uverbs_std_types_cq.c in the
> UVERBS_HANDLER(UVERBS_METHOD_CQ_CREATE) function. We check that:
>
> if (attr.comp_vector >= attrs->ufile->device->num_comp_vectors) {
>
> But we don't check that "attr.comp_vector" whether negative. It
> could potentially lead to an array underflow. My concern would be where
> cq->vector is used in the create_cq() function from the cxgb4 driver.
>
> Fixes: 9ee79fce3642 ("IB/core: Add completion queue (cq) object actions")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> drivers/infiniband/core/uverbs.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h
> index 1e5aeb39f774..63f7f7db5902 100644
> --- a/drivers/infiniband/core/uverbs.h
> +++ b/drivers/infiniband/core/uverbs.h
> @@ -98,7 +98,7 @@ ib_uverbs_init_udata_buf_or_null(struct ib_udata *udata,
>
> struct ib_uverbs_device {
> atomic_t refcount;
> - int num_comp_vectors;
> + u32 num_comp_vectors;
> struct completion comp;
> struct device dev;
> /* First group for device attributes, NULL terminated array */
I would have expected you to change struct ib_cq_init_attr ? Or at
least both..
This is actually a bug as the type of
UVERBS_ATTR_CREATE_CQ_COMP_VECTOR for userspace is u32:
UVERBS_ATTR_PTR_IN(UVERBS_ATTR_CREATE_CQ_COMP_VECTOR,
UVERBS_ATTR_TYPE(u32),
UA_MANDATORY),
But we are stuffing it into a int:
ret = uverbs_copy_from(&attr.comp_vector, attrs,
UVERBS_ATTR_CREATE_CQ_COMP_VECTOR);
So very large values will become negative and switching
num_comp_vectors to u32 won't help??
Jason
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] uverbs: prevent potential underflow
2019-10-08 19:44 ` Jason Gunthorpe
@ 2019-10-09 7:35 ` Dan Carpenter
2019-10-11 13:34 ` [PATCH v2] " Dan Carpenter
1 sibling, 0 replies; 5+ messages in thread
From: Dan Carpenter @ 2019-10-09 7:35 UTC (permalink / raw)
To: Jason Gunthorpe
Cc: Doug Ledford, Potnuri Bharat Teja, Matan Barak, Leon Romanovsky,
Shamir Rabinovitch, Matthew Wilcox, Michael Guralnik, linux-rdma,
linux-kernel, kernel-janitors
On Tue, Oct 08, 2019 at 04:44:25PM -0300, Jason Gunthorpe wrote:
> On Sat, Oct 05, 2019 at 08:23:37AM +0300, Dan Carpenter wrote:
> > The issue is in drivers/infiniband/core/uverbs_std_types_cq.c in the
> > UVERBS_HANDLER(UVERBS_METHOD_CQ_CREATE) function. We check that:
> >
> > if (attr.comp_vector >= attrs->ufile->device->num_comp_vectors) {
> >
> > But we don't check that "attr.comp_vector" whether negative. It
> > could potentially lead to an array underflow. My concern would be where
> > cq->vector is used in the create_cq() function from the cxgb4 driver.
> >
> > Fixes: 9ee79fce3642 ("IB/core: Add completion queue (cq) object actions")
> > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> > ---
> > drivers/infiniband/core/uverbs.h | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
>
>
> > diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h
> > index 1e5aeb39f774..63f7f7db5902 100644
> > --- a/drivers/infiniband/core/uverbs.h
> > +++ b/drivers/infiniband/core/uverbs.h
> > @@ -98,7 +98,7 @@ ib_uverbs_init_udata_buf_or_null(struct ib_udata *udata,
> >
> > struct ib_uverbs_device {
> > atomic_t refcount;
> > - int num_comp_vectors;
> > + u32 num_comp_vectors;
> > struct completion comp;
> > struct device dev;
> > /* First group for device attributes, NULL terminated array */
>
> I would have expected you to change struct ib_cq_init_attr ? Or at
> least both..
>
> This is actually a bug as the type of
> UVERBS_ATTR_CREATE_CQ_COMP_VECTOR for userspace is u32:
>
> UVERBS_ATTR_PTR_IN(UVERBS_ATTR_CREATE_CQ_COMP_VECTOR,
> UVERBS_ATTR_TYPE(u32),
> UA_MANDATORY),
>
> But we are stuffing it into a int:
>
> ret = uverbs_copy_from(&attr.comp_vector, attrs,
> UVERBS_ATTR_CREATE_CQ_COMP_VECTOR);
>
> So very large values will become negative and switching
> num_comp_vectors to u32 won't help??
Yeah. You're right. I should have changed both. I'm not sure what I
was thinking.
My patch does fix the bug because of type promotion, but we should
change both to u32.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH v2] uverbs: prevent potential underflow
2019-10-08 19:44 ` Jason Gunthorpe
2019-10-09 7:35 ` Dan Carpenter
@ 2019-10-11 13:34 ` Dan Carpenter
2019-10-22 18:15 ` Jason Gunthorpe
1 sibling, 1 reply; 5+ messages in thread
From: Dan Carpenter @ 2019-10-11 13:34 UTC (permalink / raw)
To: Doug Ledford, Matan Barak
Cc: Jason Gunthorpe, Yishai Hadas, Leon Romanovsky,
Shamir Rabinovitch, Michael Guralnik, Matthew Wilcox, linux-rdma,
kernel-janitors
The issue is in drivers/infiniband/core/uverbs_std_types_cq.c in the
UVERBS_HANDLER(UVERBS_METHOD_CQ_CREATE) function. We check that:
if (attr.comp_vector >= attrs->ufile->device->num_comp_vectors) {
But we don't check that "attr.comp_vector" whether negative. It
could potentially lead to an array underflow. My concern would be where
cq->vector is used in the create_cq() function from the cxgb4 driver.
And really "attr.comp_vector" is appears as a u32 to user space so that's
the right type to use.
Fixes: 9ee79fce3642 ("IB/core: Add completion queue (cq) object actions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v2: Change both types to u32
drivers/infiniband/core/uverbs.h | 2 +-
include/rdma/ib_verbs.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h
index 1e5aeb39f774..63f7f7db5902 100644
--- a/drivers/infiniband/core/uverbs.h
+++ b/drivers/infiniband/core/uverbs.h
@@ -98,7 +98,7 @@ ib_uverbs_init_udata_buf_or_null(struct ib_udata *udata,
struct ib_uverbs_device {
atomic_t refcount;
- int num_comp_vectors;
+ u32 num_comp_vectors;
struct completion comp;
struct device dev;
/* First group for device attributes, NULL terminated array */
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 6a47ba85c54c..e7e733add99f 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -366,7 +366,7 @@ struct ib_tm_caps {
struct ib_cq_init_attr {
unsigned int cqe;
- int comp_vector;
+ u32 comp_vector;
u32 flags;
};
--
2.20.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH v2] uverbs: prevent potential underflow
2019-10-11 13:34 ` [PATCH v2] " Dan Carpenter
@ 2019-10-22 18:15 ` Jason Gunthorpe
0 siblings, 0 replies; 5+ messages in thread
From: Jason Gunthorpe @ 2019-10-22 18:15 UTC (permalink / raw)
To: Dan Carpenter
Cc: Doug Ledford, Matan Barak, Yishai Hadas, Leon Romanovsky,
Shamir Rabinovitch, Michael Guralnik, Matthew Wilcox, linux-rdma,
kernel-janitors
On Fri, Oct 11, 2019 at 04:34:19PM +0300, Dan Carpenter wrote:
> The issue is in drivers/infiniband/core/uverbs_std_types_cq.c in the
> UVERBS_HANDLER(UVERBS_METHOD_CQ_CREATE) function. We check that:
>
> if (attr.comp_vector >= attrs->ufile->device->num_comp_vectors) {
>
> But we don't check that "attr.comp_vector" whether negative. It
> could potentially lead to an array underflow. My concern would be where
> cq->vector is used in the create_cq() function from the cxgb4 driver.
>
> And really "attr.comp_vector" is appears as a u32 to user space so that's
> the right type to use.
>
> Fixes: 9ee79fce3642 ("IB/core: Add completion queue (cq) object actions")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> v2: Change both types to u32
>
> drivers/infiniband/core/uverbs.h | 2 +-
> include/rdma/ib_verbs.h | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
Applied to for-rc, thanks
Jason
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2019-10-22 18:16 UTC | newest]
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2019-10-05 5:23 [PATCH] uverbs: prevent potential underflow Dan Carpenter
2019-10-08 19:44 ` Jason Gunthorpe
2019-10-09 7:35 ` Dan Carpenter
2019-10-11 13:34 ` [PATCH v2] " Dan Carpenter
2019-10-22 18:15 ` Jason Gunthorpe
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