2020-11-12 14:59:27

by Yue Haibing

Subject: [PATCH] IB/srpt: Fix passing zero to 'PTR_ERR'

Fix smatch warning:

drivers/infiniband/ulp/srpt/ib_srpt.c:2341 srpt_cm_req_recv() warn: passing zero to 'PTR_ERR'

Use PTR_ERR_OR_ZERO instead of PTR_ERR

Fixes: 847462de3a0a ("IB/srpt: Fix srpt_cm_req_recv() error path (1/2)")
Signed-off-by: YueHaibing <[email protected]>
---
drivers/infiniband/ulp/srpt/ib_srpt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 6be60aa5ffe2..3ff24b5048ac 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -2338,7 +2338,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,

if (IS_ERR_OR_NULL(ch->sess)) {
WARN_ON_ONCE(ch->sess == NULL);
- ret = PTR_ERR(ch->sess);
+ ret = PTR_ERR_OR_ZERO(ch->sess);
ch->sess = NULL;
pr_info("Rejected login for initiator %s: ret = %d.\n",
ch->sess_name, ret);
--
2.17.1

2020-11-12 17:22:52

by Jason Gunthorpe

Subject: Re: [PATCH] IB/srpt: Fix passing zero to 'PTR_ERR'

On Thu, Nov 12, 2020 at 10:54:43PM +0800, YueHaibing wrote:
> Fix smatch warning:
>
> drivers/infiniband/ulp/srpt/ib_srpt.c:2341 srpt_cm_req_recv() warn: passing zero to 'PTR_ERR'
>
> Use PTR_ERR_OR_ZERO instead of PTR_ERR
>
> Fixes: 847462de3a0a ("IB/srpt: Fix srpt_cm_req_recv() error path (1/2)")
> Signed-off-by: YueHaibing <[email protected]>
> drivers/infiniband/ulp/srpt/ib_srpt.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
> index 6be60aa5ffe2..3ff24b5048ac 100644
> +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
> @@ -2338,7 +2338,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
>
> if (IS_ERR_OR_NULL(ch->sess)) {
> WARN_ON_ONCE(ch->sess == NULL);
> - ret = PTR_ERR(ch->sess);
> + ret = PTR_ERR_OR_ZERO(ch->sess);
> ch->sess = NULL;
> pr_info("Rejected login for initiator %s: ret = %d.\n",
> ch->sess_name, ret);

I think it should be like this, Bart?

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 6017d525084a0c..80f9673956ced2 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -2311,7 +2311,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,

mutex_lock(&sport->port_guid_id.mutex);
list_for_each_entry(stpg, &sport->port_guid_id.tpg_list, entry) {
- if (!IS_ERR_OR_NULL(ch->sess))
+ if (ch->sess)
break;
ch->sess = target_setup_session(&stpg->tpg, tag_num,
tag_size, TARGET_PROT_NORMAL,
@@ -2321,12 +2321,12 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,

mutex_lock(&sport->port_gid_id.mutex);
list_for_each_entry(stpg, &sport->port_gid_id.tpg_list, entry) {
- if (!IS_ERR_OR_NULL(ch->sess))
+ if (ch->sess)
break;
ch->sess = target_setup_session(&stpg->tpg, tag_num,
tag_size, TARGET_PROT_NORMAL, i_port_id,
ch, NULL);
- if (!IS_ERR_OR_NULL(ch->sess))
+ if (ch->sess)
break;
/* Retry without leading "0x" */
ch->sess = target_setup_session(&stpg->tpg, tag_num,
@@ -2335,7 +2335,9 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
}
mutex_unlock(&sport->port_gid_id.mutex);

- if (IS_ERR_OR_NULL(ch->sess)) {
+ if (!ch->sess)
+ ch->sess = ERR_PTR(-ENOENT);
+ if (IS_ERR(ch->sess)) {
WARN_ON_ONCE(ch->sess == NULL);
ret = PTR_ERR(ch->sess);
ch->sess = NULL;

2020-11-12 18:28:43

by Bart Van Assche

Subject: Re: [PATCH] IB/srpt: Fix passing zero to 'PTR_ERR'

On 11/12/20 9:20 AM, Jason Gunthorpe wrote:
> I think it should be like this, Bart?
>
> diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
> index 6017d525084a0c..80f9673956ced2 100644
> --- a/drivers/infiniband/ulp/srpt/ib_srpt.c
> +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
> @@ -2311,7 +2311,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
>
> mutex_lock(&sport->port_guid_id.mutex);
> list_for_each_entry(stpg, &sport->port_guid_id.tpg_list, entry) {
> - if (!IS_ERR_OR_NULL(ch->sess))
> + if (ch->sess)
> break;
> ch->sess = target_setup_session(&stpg->tpg, tag_num,
> tag_size, TARGET_PROT_NORMAL,
> @@ -2321,12 +2321,12 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
>
> mutex_lock(&sport->port_gid_id.mutex);
> list_for_each_entry(stpg, &sport->port_gid_id.tpg_list, entry) {
> - if (!IS_ERR_OR_NULL(ch->sess))
> + if (ch->sess)
> break;
> ch->sess = target_setup_session(&stpg->tpg, tag_num,
> tag_size, TARGET_PROT_NORMAL, i_port_id,
> ch, NULL);
> - if (!IS_ERR_OR_NULL(ch->sess))
> + if (ch->sess)
> break;
> /* Retry without leading "0x" */
> ch->sess = target_setup_session(&stpg->tpg, tag_num,
> @@ -2335,7 +2335,9 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
> }
> mutex_unlock(&sport->port_gid_id.mutex);
>
> - if (IS_ERR_OR_NULL(ch->sess)) {
> + if (!ch->sess)
> + ch->sess = ERR_PTR(-ENOENT);
> + if (IS_ERR(ch->sess)) {
> WARN_ON_ONCE(ch->sess == NULL);
> ret = PTR_ERR(ch->sess);
> ch->sess = NULL;
>

Hi Jason,

The ib_srpt driver accepts three different formats for the initiator
ACL. Up to two of the three target_setup_session() calls will fail if
the fifth argument of target_setup_session() does not use the format of
the initiator ID in configfs. If the first or the second
target_setup_session() call fails it is essential that later
target_setup_session() calls happen. Hence the IS_ERR_OR_NULL(ch->sess)
checks in the above loops.

In other words, I like YueHaibing's patch better.

Thanks,

Bart.

2020-11-12 18:32:47

by Jason Gunthorpe

Subject: Re: [PATCH] IB/srpt: Fix passing zero to 'PTR_ERR'

On Thu, Nov 12, 2020 at 10:25:48AM -0800, Bart Van Assche wrote:
> On 11/12/20 9:20 AM, Jason Gunthorpe wrote:
> > I think it should be like this, Bart?
> >
> > diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
> > index 6017d525084a0c..80f9673956ced2 100644
> > +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
> > @@ -2311,7 +2311,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
> > mutex_lock(&sport->port_guid_id.mutex);
> > list_for_each_entry(stpg, &sport->port_guid_id.tpg_list, entry) {
> > - if (!IS_ERR_OR_NULL(ch->sess))
> > + if (ch->sess)
> > break;
> > ch->sess = target_setup_session(&stpg->tpg, tag_num,
> > tag_size, TARGET_PROT_NORMAL,
> > @@ -2321,12 +2321,12 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
> > mutex_lock(&sport->port_gid_id.mutex);
> > list_for_each_entry(stpg, &sport->port_gid_id.tpg_list, entry) {
> > - if (!IS_ERR_OR_NULL(ch->sess))
> > + if (ch->sess)
> > break;
> > ch->sess = target_setup_session(&stpg->tpg, tag_num,
> > tag_size, TARGET_PROT_NORMAL, i_port_id,
> > ch, NULL);
> > - if (!IS_ERR_OR_NULL(ch->sess))
> > + if (ch->sess)
> > break;
> > /* Retry without leading "0x" */
> > ch->sess = target_setup_session(&stpg->tpg, tag_num,
> > @@ -2335,7 +2335,9 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
> > }
> > mutex_unlock(&sport->port_gid_id.mutex);
> > - if (IS_ERR_OR_NULL(ch->sess)) {
> > + if (!ch->sess)
> > + ch->sess = ERR_PTR(-ENOENT);
> > + if (IS_ERR(ch->sess)) {
> > WARN_ON_ONCE(ch->sess == NULL);
> > ret = PTR_ERR(ch->sess);
> > ch->sess = NULL;
> >
>
> Hi Jason,
>
> The ib_srpt driver accepts three different formats for the initiator ACL. Up
> to two of the three target_setup_session() calls will fail if the fifth
> argument of target_setup_session() does not use the format of the initiator
> ID in configfs. If the first or the second target_setup_session() call fails
> it is essential that later target_setup_session() calls happen. Hence the
> IS_ERR_OR_NULL(ch->sess) checks in the above loops.

IS_ERR_OR_NULL is an abomination, it should not be used.

I see I didn't quite get it right, but that is still closer to sane,
probably target_setup_session() should return NULL not err_ptr

Jason

2021-05-14 14:57:44

by Yue Haibing

Subject: Re: [PATCH] IB/srpt: Fix passing zero to 'PTR_ERR'

On 2020/11/13 2:30, Jason Gunthorpe wrote:
> On Thu, Nov 12, 2020 at 10:25:48AM -0800, Bart Van Assche wrote:
>> On 11/12/20 9:20 AM, Jason Gunthorpe wrote:
>>> I think it should be like this, Bart?
>>>
>>> diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
>>> index 6017d525084a0c..80f9673956ced2 100644
>>> +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
>>> @@ -2311,7 +2311,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
>>> mutex_lock(&sport->port_guid_id.mutex);
>>> list_for_each_entry(stpg, &sport->port_guid_id.tpg_list, entry) {
>>> - if (!IS_ERR_OR_NULL(ch->sess))
>>> + if (ch->sess)
>>> break;
>>> ch->sess = target_setup_session(&stpg->tpg, tag_num,
>>> tag_size, TARGET_PROT_NORMAL,
>>> @@ -2321,12 +2321,12 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
>>> mutex_lock(&sport->port_gid_id.mutex);
>>> list_for_each_entry(stpg, &sport->port_gid_id.tpg_list, entry) {
>>> - if (!IS_ERR_OR_NULL(ch->sess))
>>> + if (ch->sess)
>>> break;
>>> ch->sess = target_setup_session(&stpg->tpg, tag_num,
>>> tag_size, TARGET_PROT_NORMAL, i_port_id,
>>> ch, NULL);
>>> - if (!IS_ERR_OR_NULL(ch->sess))
>>> + if (ch->sess)
>>> break;
>>> /* Retry without leading "0x" */
>>> ch->sess = target_setup_session(&stpg->tpg, tag_num,
>>> @@ -2335,7 +2335,9 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
>>> }
>>> mutex_unlock(&sport->port_gid_id.mutex);
>>> - if (IS_ERR_OR_NULL(ch->sess)) {
>>> + if (!ch->sess)
>>> + ch->sess = ERR_PTR(-ENOENT);
>>> + if (IS_ERR(ch->sess)) {
>>> WARN_ON_ONCE(ch->sess == NULL);
>>> ret = PTR_ERR(ch->sess);
>>> ch->sess = NULL;
>>>
>>
>> Hi Jason,
>>
>> The ib_srpt driver accepts three different formats for the initiator ACL. Up
>> to two of the three target_setup_session() calls will fail if the fifth
>> argument of target_setup_session() does not use the format of the initiator
>> ID in configfs. If the first or the second target_setup_session() call fails
>> it is essential that later target_setup_session() calls happen. Hence the
>> IS_ERR_OR_NULL(ch->sess) checks in the above loops.
>
> IS_ERR_OR_NULL is an abomination, it should not be used.
>
> I see I didn't quite get it right, but that is still closer to sane,
> probably target_setup_session() should return NULL not err_ptr

Any fix plan?

>
> Jason
> .
>