diff mbox

[v2] infiniband: remove WARN that is not kernel bug

Message ID 20161121114417.GA4158@leon.nu
State Superseded
Headers show

Commit Message

Leon Romanovsky Nov. 21, 2016, 11:44 a.m. UTC 
On Mon, Nov 21, 2016 at 11:30:21AM +0100, Dmitry Vyukov wrote:
> On Mon, Nov 21, 2016 at 11:25 AM, Miroslav Benes <mbenes@suse.cz> wrote:

> > On Mon, 21 Nov 2016, Dmitry Vyukov wrote:

> >

> >> WARNINGs mean kernel bugs.

> >> The one in ucma_write() points to user programming error

> >> or a malicious attempt. This is not a kernel bug, remove it.

> >>

> >> BUG/WARNs that are not kernel bugs hinder automated testing effots.

> >>

> >> Signed-off-by: Dmitry Vyukov <dvyukov@google.com>

> >> Cc: Doug Ledford <dledford@redhat.com>

> >> Cc: Sean Hefty <sean.hefty@intel.com>

> >> Cc: Hal Rosenstock <hal.rosenstock@gmail.com>

> >> Cc: Leon Romanovsky <leon@kernel.org>

> >> Cc: linux-rdma@vger.kernel.org

> >> Cc: linux-kernel@vger.kernel.org

> >> Cc: syzkaller@googlegroups.com

> >>

> >> ---

> >> Changes since v1:

> >>  - added printk_once

> >> ---

> >>  drivers/infiniband/core/ucma.c | 5 ++++-

> >>  1 file changed, 4 insertions(+), 1 deletion(-)

> >>

> >> diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c

> >> index 9520154..405d0ce 100644

> >> --- a/drivers/infiniband/core/ucma.c

> >> +++ b/drivers/infiniband/core/ucma.c

> >> @@ -1584,8 +1584,11 @@ static ssize_t ucma_write(struct file *filp, const char __user *buf,

> >>       struct rdma_ucm_cmd_hdr hdr;

> >>       ssize_t ret;

> >>

> >> -     if (WARN_ON_ONCE(!ib_safe_file_access(filp)))

> >> +     if (!ib_safe_file_access(filp)) {

> >> +             printk_once("ucma_write: process %d (%s) tried to do something hinky\n",

> >> +                     task_tgid_vnr(current), current->comm);

> >>               return -EACCES;

> >> +     }

> >>

> >>       if (len < sizeof(hdr))

> >>               return -EINVAL;

> >

> > FWIW, WARN_ON_ONCE came with commit e6bd18f57aad ("IB/security: Restrict

> > use of the write() interface"). Would it make sense to change the other

> > places as well?

>

>

> I guess so.

> Can I ask somebody of infiniband maintainers to take care of this?


Please see below,
Hope it helps.


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Comments

Dmitry Vyukov Nov. 21, 2016, 11:48 a.m. UTC | #1 
On Mon, Nov 21, 2016 at 12:44 PM, Leon Romanovsky <leon@kernel.org> wrote:
> On Mon, Nov 21, 2016 at 11:30:21AM +0100, Dmitry Vyukov wrote:

>> On Mon, Nov 21, 2016 at 11:25 AM, Miroslav Benes <mbenes@suse.cz> wrote:

>> > On Mon, 21 Nov 2016, Dmitry Vyukov wrote:

>> >

>> >> WARNINGs mean kernel bugs.

>> >> The one in ucma_write() points to user programming error

>> >> or a malicious attempt. This is not a kernel bug, remove it.

>> >>

>> >> BUG/WARNs that are not kernel bugs hinder automated testing effots.

>> >>

>> >> Signed-off-by: Dmitry Vyukov <dvyukov@google.com>

>> >> Cc: Doug Ledford <dledford@redhat.com>

>> >> Cc: Sean Hefty <sean.hefty@intel.com>

>> >> Cc: Hal Rosenstock <hal.rosenstock@gmail.com>

>> >> Cc: Leon Romanovsky <leon@kernel.org>

>> >> Cc: linux-rdma@vger.kernel.org

>> >> Cc: linux-kernel@vger.kernel.org

>> >> Cc: syzkaller@googlegroups.com

>> >>

>> >> ---

>> >> Changes since v1:

>> >>  - added printk_once

>> >> ---

>> >>  drivers/infiniband/core/ucma.c | 5 ++++-

>> >>  1 file changed, 4 insertions(+), 1 deletion(-)

>> >>

>> >> diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c

>> >> index 9520154..405d0ce 100644

>> >> --- a/drivers/infiniband/core/ucma.c

>> >> +++ b/drivers/infiniband/core/ucma.c

>> >> @@ -1584,8 +1584,11 @@ static ssize_t ucma_write(struct file *filp, const char __user *buf,

>> >>       struct rdma_ucm_cmd_hdr hdr;

>> >>       ssize_t ret;

>> >>

>> >> -     if (WARN_ON_ONCE(!ib_safe_file_access(filp)))

>> >> +     if (!ib_safe_file_access(filp)) {

>> >> +             printk_once("ucma_write: process %d (%s) tried to do something hinky\n",

>> >> +                     task_tgid_vnr(current), current->comm);

>> >>               return -EACCES;

>> >> +     }

>> >>

>> >>       if (len < sizeof(hdr))

>> >>               return -EINVAL;

>> >

>> > FWIW, WARN_ON_ONCE came with commit e6bd18f57aad ("IB/security: Restrict

>> > use of the write() interface"). Would it make sense to change the other

>> > places as well?

>>

>>

>> I guess so.

>> Can I ask somebody of infiniband maintainers to take care of this?

>

> Please see below,

> Hope it helps.


In ib_ucm_write function there is a wrong prefix:

+ pr_err_once("ucm_write: process %d (%s) tried to do something hinky\n",

Otherwise looks good. Thanks.
Leon Romanovsky Nov. 21, 2016, 12:14 p.m. UTC | #2 
On Mon, Nov 21, 2016 at 12:48:35PM +0100, Dmitry Vyukov wrote:
> On Mon, Nov 21, 2016 at 12:44 PM, Leon Romanovsky <leon@kernel.org> wrote:

> > On Mon, Nov 21, 2016 at 11:30:21AM +0100, Dmitry Vyukov wrote:

> >> On Mon, Nov 21, 2016 at 11:25 AM, Miroslav Benes <mbenes@suse.cz> wrote:

> >> > On Mon, 21 Nov 2016, Dmitry Vyukov wrote:

> >> >

> >> >> WARNINGs mean kernel bugs.

> >> >> The one in ucma_write() points to user programming error

> >> >> or a malicious attempt. This is not a kernel bug, remove it.

> >> >>

> >> >> BUG/WARNs that are not kernel bugs hinder automated testing effots.

> >> >>

> >> >> Signed-off-by: Dmitry Vyukov <dvyukov@google.com>

> >> >> Cc: Doug Ledford <dledford@redhat.com>

> >> >> Cc: Sean Hefty <sean.hefty@intel.com>

> >> >> Cc: Hal Rosenstock <hal.rosenstock@gmail.com>

> >> >> Cc: Leon Romanovsky <leon@kernel.org>

> >> >> Cc: linux-rdma@vger.kernel.org

> >> >> Cc: linux-kernel@vger.kernel.org

> >> >> Cc: syzkaller@googlegroups.com

> >> >>

> >> >> ---

> >> >> Changes since v1:

> >> >>  - added printk_once

> >> >> ---

> >> >>  drivers/infiniband/core/ucma.c | 5 ++++-

> >> >>  1 file changed, 4 insertions(+), 1 deletion(-)

> >> >>

> >> >> diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c

> >> >> index 9520154..405d0ce 100644

> >> >> --- a/drivers/infiniband/core/ucma.c

> >> >> +++ b/drivers/infiniband/core/ucma.c

> >> >> @@ -1584,8 +1584,11 @@ static ssize_t ucma_write(struct file *filp, const char __user *buf,

> >> >>       struct rdma_ucm_cmd_hdr hdr;

> >> >>       ssize_t ret;

> >> >>

> >> >> -     if (WARN_ON_ONCE(!ib_safe_file_access(filp)))

> >> >> +     if (!ib_safe_file_access(filp)) {

> >> >> +             printk_once("ucma_write: process %d (%s) tried to do something hinky\n",

> >> >> +                     task_tgid_vnr(current), current->comm);

> >> >>               return -EACCES;

> >> >> +     }

> >> >>

> >> >>       if (len < sizeof(hdr))

> >> >>               return -EINVAL;

> >> >

> >> > FWIW, WARN_ON_ONCE came with commit e6bd18f57aad ("IB/security: Restrict

> >> > use of the write() interface"). Would it make sense to change the other

> >> > places as well?

> >>

> >>

> >> I guess so.

> >> Can I ask somebody of infiniband maintainers to take care of this?

> >

> > Please see below,

> > Hope it helps.

>

> In ib_ucm_write function there is a wrong prefix:

>

> + pr_err_once("ucm_write: process %d (%s) tried to do something hinky\n",


I did it intentionally to have the same errors for all flows.

>

> Otherwise looks good. Thanks.
Jason Gunthorpe Nov. 21, 2016, 4:52 p.m. UTC | #3 
On Mon, Nov 21, 2016 at 02:14:08PM +0200, Leon Romanovsky wrote:
> >

> > In ib_ucm_write function there is a wrong prefix:

> >

> > + pr_err_once("ucm_write: process %d (%s) tried to do something hinky\n",

> 

> I did it intentionally to have the same errors for all flows.


Lets actually use a good message too please?

 pr_err_once("ucm_write: process %d (%s) changed security contexts after opening FD, this is not allowed.\n",

Jason
diff mbox

Patch

From e0bfe4771591f9ffbcaa4e66d6257ed95e2d7188 Mon Sep 17 00:00:00 2001
From: Leon Romanovsky <leonro@mellanox.com>
Date: Mon, 21 Nov 2016 13:30:59 +0200
Subject: [PATCH] IB/{core, qib}: Remove WARN that is not kernel bug

WARNINGs mean kernel bugs, in this case, they are placed
to mark programming errors and/or malicious attempts.

BUG/WARNs that are not kernel bugs hinder automated testing efforts.

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/core/ucm.c            | 5 ++++-
 drivers/infiniband/core/ucma.c           | 5 ++++-
 drivers/infiniband/core/uverbs_main.c    | 5 ++++-
 drivers/infiniband/hw/qib/qib_file_ops.c | 5 ++++-
 4 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/core/ucm.c b/drivers/infiniband/core/ucm.c
index 7713ef0..0076b55 100644
--- a/drivers/infiniband/core/ucm.c
+++ b/drivers/infiniband/core/ucm.c
@@ -1104,8 +1104,11 @@  static ssize_t ib_ucm_write(struct file *filp, const char __user *buf,
 	struct ib_ucm_cmd_hdr hdr;
 	ssize_t result;

-	if (WARN_ON_ONCE(!ib_safe_file_access(filp)))
+	if (!ib_safe_file_access(filp)) {
+		pr_err_once("ucm_write: process %d (%s) tried to do something hinky\n",
+			    task_tgid_vnr(current), current->comm);
 		return -EACCES;
+	}

 	if (len < sizeof(hdr))
 		return -EINVAL;
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index 9520154..31fa27f 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -1584,8 +1584,11 @@  static ssize_t ucma_write(struct file *filp, const char __user *buf,
 	struct rdma_ucm_cmd_hdr hdr;
 	ssize_t ret;

-	if (WARN_ON_ONCE(!ib_safe_file_access(filp)))
+	if (!ib_safe_file_access(filp)) {
+		pr_err_once("ucma_write: process %d (%s) tried to do something hinky\n",
+			    task_tgid_vnr(current), current->comm);
 		return -EACCES;
+	}

 	if (len < sizeof(hdr))
 		return -EINVAL;
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index 44b1104..329eb15 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -746,8 +746,11 @@  static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 	int srcu_key;
 	ssize_t ret;

-	if (WARN_ON_ONCE(!ib_safe_file_access(filp)))
+	if (!ib_safe_file_access(filp)) {
+		pr_err_once("uverbs_write: process %d (%s) tried to do something hinky\n",
+			    task_tgid_vnr(current), current->comm);
 		return -EACCES;
+	}

 	if (count < sizeof hdr)
 		return -EINVAL;
diff --git a/drivers/infiniband/hw/qib/qib_file_ops.c b/drivers/infiniband/hw/qib/qib_file_ops.c
index 382466a..b43ea52 100644
--- a/drivers/infiniband/hw/qib/qib_file_ops.c
+++ b/drivers/infiniband/hw/qib/qib_file_ops.c
@@ -2066,8 +2066,11 @@  static ssize_t qib_write(struct file *fp, const char __user *data,
 	ssize_t ret = 0;
 	void *dest;

-	if (WARN_ON_ONCE(!ib_safe_file_access(fp)))
+	if (!ib_safe_file_access(fp)) {
+		pr_err_once("qib_write: process %d (%s) tried to do something hinky\n",
+			    task_tgid_vnr(current), current->comm);
 		return -EACCES;
+	}

 	if (count < sizeof(cmd.type)) {
 		ret = -EINVAL;
--
2.7.4