* [bug report] block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
@ 2020-12-08 12:15 Dan Carpenter
2020-12-08 13:20 ` Haris Iqbal
0 siblings, 1 reply; 5+ messages in thread
From: Dan Carpenter @ 2020-12-08 12:15 UTC (permalink / raw)
To: haris.iqbal; +Cc: linux-block
Hello Md Haris Iqbal,
This is a semi-automatic email about new static checker warnings.
The patch 64e8a6ece1a5: "block/rnbd-clt: Dynamically alloc buffer for
pathname & blk_symlink_name" from Nov 26, 2020, leads to the
following Smatch complaint:
drivers/block/rnbd/rnbd-clt-sysfs.c:525 rnbd_clt_add_dev_symlink()
error: uninitialized symbol 'ret'.
drivers/block/rnbd/rnbd-clt-sysfs.c:524 rnbd_clt_add_dev_symlink()
error: we previously assumed 'dev->blk_symlink_name' could be null (see line 500)
drivers/block/rnbd/rnbd-clt-sysfs.c
493 static int rnbd_clt_add_dev_symlink(struct rnbd_clt_dev *dev)
494 {
495 struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
496 int ret, len;
497
498 len = strlen(dev->pathname) + strlen(dev->sess->sessname) + 2;
499 dev->blk_symlink_name = kzalloc(len, GFP_KERNEL);
500 if (!dev->blk_symlink_name) {
501 rnbd_clt_err(dev, "Failed to allocate memory for blk_symlink_name\n");
502 goto out_err;
ret = -ENOMEM; here
503 }
504
505 ret = rnbd_clt_get_path_name(dev, dev->blk_symlink_name,
506 len);
507 if (ret) {
508 rnbd_clt_err(dev, "Failed to get /sys/block symlink path, err: %d\n",
509 ret);
510 goto out_err;
511 }
512
513 ret = sysfs_create_link(rnbd_devs_kobj, gd_kobj,
514 dev->blk_symlink_name);
515 if (ret) {
516 rnbd_clt_err(dev, "Creating /sys/block symlink failed, err: %d\n",
517 ret);
518 goto out_err;
519 }
520
521 return 0;
522
523 out_err:
524 dev->blk_symlink_name[0] = '\0';
^^^^^^^^^^^^^^^^^^^^^^^^
This will oops if the kzalloc() fails.
525 return ret;
526 }
regards,
dan carpenter
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [bug report] block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
2020-12-08 12:15 [bug report] block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name Dan Carpenter
@ 2020-12-08 13:20 ` Haris Iqbal
2020-12-08 13:24 ` Jinpu Wang
0 siblings, 1 reply; 5+ messages in thread
From: Haris Iqbal @ 2020-12-08 13:20 UTC (permalink / raw)
To: Dan Carpenter; +Cc: linux-block, Danil Kipnis, Jinpu Wang
On Tue, Dec 8, 2020 at 5:45 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> Hello Md Haris Iqbal,
>
> This is a semi-automatic email about new static checker warnings.
>
> The patch 64e8a6ece1a5: "block/rnbd-clt: Dynamically alloc buffer for
> pathname & blk_symlink_name" from Nov 26, 2020, leads to the
> following Smatch complaint:
>
> drivers/block/rnbd/rnbd-clt-sysfs.c:525 rnbd_clt_add_dev_symlink()
> error: uninitialized symbol 'ret'.
>
> drivers/block/rnbd/rnbd-clt-sysfs.c:524 rnbd_clt_add_dev_symlink()
> error: we previously assumed 'dev->blk_symlink_name' could be null (see line 500)
>
> drivers/block/rnbd/rnbd-clt-sysfs.c
> 493 static int rnbd_clt_add_dev_symlink(struct rnbd_clt_dev *dev)
> 494 {
> 495 struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
> 496 int ret, len;
> 497
> 498 len = strlen(dev->pathname) + strlen(dev->sess->sessname) + 2;
> 499 dev->blk_symlink_name = kzalloc(len, GFP_KERNEL);
> 500 if (!dev->blk_symlink_name) {
> 501 rnbd_clt_err(dev, "Failed to allocate memory for blk_symlink_name\n");
> 502 goto out_err;
>
> ret = -ENOMEM; here
>
> 503 }
> 504
> 505 ret = rnbd_clt_get_path_name(dev, dev->blk_symlink_name,
> 506 len);
> 507 if (ret) {
> 508 rnbd_clt_err(dev, "Failed to get /sys/block symlink path, err: %d\n",
> 509 ret);
> 510 goto out_err;
> 511 }
> 512
> 513 ret = sysfs_create_link(rnbd_devs_kobj, gd_kobj,
> 514 dev->blk_symlink_name);
> 515 if (ret) {
> 516 rnbd_clt_err(dev, "Creating /sys/block symlink failed, err: %d\n",
> 517 ret);
> 518 goto out_err;
> 519 }
> 520
> 521 return 0;
> 522
> 523 out_err:
> 524 dev->blk_symlink_name[0] = '\0';
> ^^^^^^^^^^^^^^^^^^^^^^^^
> This will oops if the kzalloc() fails.
Thanks. Will send a patch soon.
>
> 525 return ret;
> 526 }
>
> regards,
> dan carpenter
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [bug report] block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
2020-12-08 13:20 ` Haris Iqbal
@ 2020-12-08 13:24 ` Jinpu Wang
2020-12-08 14:05 ` Dan Carpenter
0 siblings, 1 reply; 5+ messages in thread
From: Jinpu Wang @ 2020-12-08 13:24 UTC (permalink / raw)
To: Haris Iqbal, Dan Carpenter; +Cc: linux-block, Danil Kipnis
Hi,
On Tue, Dec 8, 2020 at 2:21 PM Haris Iqbal <haris.iqbal@cloud.ionos.com> wrote:
>
> On Tue, Dec 8, 2020 at 5:45 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
> >
> > Hello Md Haris Iqbal,
> >
> > This is a semi-automatic email about new static checker warnings.
> >
> > The patch 64e8a6ece1a5: "block/rnbd-clt: Dynamically alloc buffer for
> > pathname & blk_symlink_name" from Nov 26, 2020, leads to the
> > following Smatch complaint:
> >
> > drivers/block/rnbd/rnbd-clt-sysfs.c:525 rnbd_clt_add_dev_symlink()
> > error: uninitialized symbol 'ret'.
> >
> > drivers/block/rnbd/rnbd-clt-sysfs.c:524 rnbd_clt_add_dev_symlink()
> > error: we previously assumed 'dev->blk_symlink_name' could be null (see line 500)
> >
> > drivers/block/rnbd/rnbd-clt-sysfs.c
> > 493 static int rnbd_clt_add_dev_symlink(struct rnbd_clt_dev *dev)
> > 494 {
> > 495 struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
> > 496 int ret, len;
> > 497
> > 498 len = strlen(dev->pathname) + strlen(dev->sess->sessname) + 2;
> > 499 dev->blk_symlink_name = kzalloc(len, GFP_KERNEL);
> > 500 if (!dev->blk_symlink_name) {
> > 501 rnbd_clt_err(dev, "Failed to allocate memory for blk_symlink_name\n");
> > 502 goto out_err;
> >
> > ret = -ENOMEM; here
> >
> > 503 }
> > 504
> > 505 ret = rnbd_clt_get_path_name(dev, dev->blk_symlink_name,
> > 506 len);
> > 507 if (ret) {
> > 508 rnbd_clt_err(dev, "Failed to get /sys/block symlink path, err: %d\n",
> > 509 ret);
> > 510 goto out_err;
> > 511 }
> > 512
> > 513 ret = sysfs_create_link(rnbd_devs_kobj, gd_kobj,
> > 514 dev->blk_symlink_name);
> > 515 if (ret) {
> > 516 rnbd_clt_err(dev, "Creating /sys/block symlink failed, err: %d\n",
> > 517 ret);
> > 518 goto out_err;
> > 519 }
> > 520
> > 521 return 0;
> > 522
> > 523 out_err:
> > 524 dev->blk_symlink_name[0] = '\0';
> > ^^^^^^^^^^^^^^^^^^^^^^^^
> > This will oops if the kzalloc() fails.
>
> Thanks. Will send a patch soon.
already fixed in block tree by Colin
>https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/commit/?h=for-5.11/drivers&id=733c15bd3a944b8eeaacdddf061759b6a83dd3f4
> >
> > 525 return ret;
> > 526 }
> >
> > regards,
> > dan carpenter
Thanks!
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [bug report] block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
2020-12-08 13:24 ` Jinpu Wang
@ 2020-12-08 14:05 ` Dan Carpenter
2020-12-08 14:29 ` Jinpu Wang
0 siblings, 1 reply; 5+ messages in thread
From: Dan Carpenter @ 2020-12-08 14:05 UTC (permalink / raw)
To: Jinpu Wang; +Cc: Haris Iqbal, linux-block, Danil Kipnis
On Tue, Dec 08, 2020 at 02:24:40PM +0100, Jinpu Wang wrote:
> Hi,
>
> On Tue, Dec 8, 2020 at 2:21 PM Haris Iqbal <haris.iqbal@cloud.ionos.com> wrote:
> >
> > On Tue, Dec 8, 2020 at 5:45 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
> > >
> > > Hello Md Haris Iqbal,
> > >
> > > This is a semi-automatic email about new static checker warnings.
> > >
> > > The patch 64e8a6ece1a5: "block/rnbd-clt: Dynamically alloc buffer for
> > > pathname & blk_symlink_name" from Nov 26, 2020, leads to the
> > > following Smatch complaint:
> > >
> > > drivers/block/rnbd/rnbd-clt-sysfs.c:525 rnbd_clt_add_dev_symlink()
> > > error: uninitialized symbol 'ret'.
> > >
> > > drivers/block/rnbd/rnbd-clt-sysfs.c:524 rnbd_clt_add_dev_symlink()
> > > error: we previously assumed 'dev->blk_symlink_name' could be null (see line 500)
> > >
> > > drivers/block/rnbd/rnbd-clt-sysfs.c
> > > 493 static int rnbd_clt_add_dev_symlink(struct rnbd_clt_dev *dev)
> > > 494 {
> > > 495 struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
> > > 496 int ret, len;
> > > 497
> > > 498 len = strlen(dev->pathname) + strlen(dev->sess->sessname) + 2;
> > > 499 dev->blk_symlink_name = kzalloc(len, GFP_KERNEL);
> > > 500 if (!dev->blk_symlink_name) {
> > > 501 rnbd_clt_err(dev, "Failed to allocate memory for blk_symlink_name\n");
> > > 502 goto out_err;
> > >
> > > ret = -ENOMEM; here
> > >
> > > 503 }
> > > 504
> > > 505 ret = rnbd_clt_get_path_name(dev, dev->blk_symlink_name,
> > > 506 len);
> > > 507 if (ret) {
> > > 508 rnbd_clt_err(dev, "Failed to get /sys/block symlink path, err: %d\n",
> > > 509 ret);
> > > 510 goto out_err;
> > > 511 }
> > > 512
> > > 513 ret = sysfs_create_link(rnbd_devs_kobj, gd_kobj,
> > > 514 dev->blk_symlink_name);
> > > 515 if (ret) {
> > > 516 rnbd_clt_err(dev, "Creating /sys/block symlink failed, err: %d\n",
> > > 517 ret);
> > > 518 goto out_err;
> > > 519 }
> > > 520
> > > 521 return 0;
> > > 522
> > > 523 out_err:
> > > 524 dev->blk_symlink_name[0] = '\0';
> > > ^^^^^^^^^^^^^^^^^^^^^^^^
> > > This will oops if the kzalloc() fails.
> >
> > Thanks. Will send a patch soon.
> already fixed in block tree by Colin
> >https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/commit/?h=for-5.11/drivers&id=733c15bd3a944b8eeaacdddf061759b6a83dd3f4
It's a weird thing that we don't free dev->blk_symlink_name if there
is an error. It's impossible for rnbd_clt_get_path_name() to actually
return an error in the current code, but if it did then only the last
character of dev->blk_symlink_name[] is initialized.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [bug report] block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
2020-12-08 14:05 ` Dan Carpenter
@ 2020-12-08 14:29 ` Jinpu Wang
0 siblings, 0 replies; 5+ messages in thread
From: Jinpu Wang @ 2020-12-08 14:29 UTC (permalink / raw)
To: Dan Carpenter; +Cc: Haris Iqbal, linux-block, Danil Kipnis
On Tue, Dec 8, 2020 at 3:08 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> On Tue, Dec 08, 2020 at 02:24:40PM +0100, Jinpu Wang wrote:
> > Hi,
> >
> > On Tue, Dec 8, 2020 at 2:21 PM Haris Iqbal <haris.iqbal@cloud.ionos.com> wrote:
> > >
> > > On Tue, Dec 8, 2020 at 5:45 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
> > > >
> > > > Hello Md Haris Iqbal,
> > > >
> > > > This is a semi-automatic email about new static checker warnings.
> > > >
> > > > The patch 64e8a6ece1a5: "block/rnbd-clt: Dynamically alloc buffer for
> > > > pathname & blk_symlink_name" from Nov 26, 2020, leads to the
> > > > following Smatch complaint:
> > > >
> > > > drivers/block/rnbd/rnbd-clt-sysfs.c:525 rnbd_clt_add_dev_symlink()
> > > > error: uninitialized symbol 'ret'.
> > > >
> > > > drivers/block/rnbd/rnbd-clt-sysfs.c:524 rnbd_clt_add_dev_symlink()
> > > > error: we previously assumed 'dev->blk_symlink_name' could be null (see line 500)
> > > >
> > > > drivers/block/rnbd/rnbd-clt-sysfs.c
> > > > 493 static int rnbd_clt_add_dev_symlink(struct rnbd_clt_dev *dev)
> > > > 494 {
> > > > 495 struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
> > > > 496 int ret, len;
> > > > 497
> > > > 498 len = strlen(dev->pathname) + strlen(dev->sess->sessname) + 2;
> > > > 499 dev->blk_symlink_name = kzalloc(len, GFP_KERNEL);
> > > > 500 if (!dev->blk_symlink_name) {
> > > > 501 rnbd_clt_err(dev, "Failed to allocate memory for blk_symlink_name\n");
> > > > 502 goto out_err;
> > > >
> > > > ret = -ENOMEM; here
> > > >
> > > > 503 }
> > > > 504
> > > > 505 ret = rnbd_clt_get_path_name(dev, dev->blk_symlink_name,
> > > > 506 len);
> > > > 507 if (ret) {
> > > > 508 rnbd_clt_err(dev, "Failed to get /sys/block symlink path, err: %d\n",
> > > > 509 ret);
> > > > 510 goto out_err;
> > > > 511 }
> > > > 512
> > > > 513 ret = sysfs_create_link(rnbd_devs_kobj, gd_kobj,
> > > > 514 dev->blk_symlink_name);
> > > > 515 if (ret) {
> > > > 516 rnbd_clt_err(dev, "Creating /sys/block symlink failed, err: %d\n",
> > > > 517 ret);
> > > > 518 goto out_err;
> > > > 519 }
> > > > 520
> > > > 521 return 0;
> > > > 522
> > > > 523 out_err:
> > > > 524 dev->blk_symlink_name[0] = '\0';
> > > > ^^^^^^^^^^^^^^^^^^^^^^^^
> > > > This will oops if the kzalloc() fails.
> > >
> > > Thanks. Will send a patch soon.
> > already fixed in block tree by Colin
> > >https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/commit/?h=for-5.11/drivers&id=733c15bd3a944b8eeaacdddf061759b6a83dd3f4
>
> It's a weird thing that we don't free dev->blk_symlink_name if there
> is an error. It's impossible for rnbd_clt_get_path_name() to actually
> return an error in the current code, but if it did then only the last
> character of dev->blk_symlink_name[] is initialized.
right, will send out a fix soon.
>
> regards,
> dan carpenter
>
Thanks!
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2020-12-08 14:30 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2020-12-08 12:15 [bug report] block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name Dan Carpenter
2020-12-08 13:20 ` Haris Iqbal
2020-12-08 13:24 ` Jinpu Wang
2020-12-08 14:05 ` Dan Carpenter
2020-12-08 14:29 ` Jinpu Wang
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).