2020-05-18 07:51:29

by yebin (H)

Subject: [PATCH] scsi: Fix incorrect usage of shost_for_each_device

shost_for_each_device(sdev, shost) \
for ((sdev) = __scsi_iterate_devices((shost), NULL); \
(sdev); \
(sdev) = __scsi_iterate_devices((shost), (sdev)))

When terminating shost_for_each_device() iteration with break or return,
scsi_device_put() should be used to prevent stale scsi device references from
being left behind.

Signed-off-by: Ye Bin <[email protected]>
---
drivers/scsi/scsi_error.c | 2 ++
drivers/scsi/scsi_lib.c | 4 +++-
2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 978be1602f71..927b1e641842 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1412,6 +1412,7 @@ static int scsi_eh_stu(struct Scsi_Host *shost,
sdev_printk(KERN_INFO, sdev,
"%s: skip START_UNIT, past eh deadline\n",
current->comm));
+ scsi_device_put(sdev);
break;
}
stu_scmd = NULL;
@@ -1478,6 +1479,7 @@ static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
sdev_printk(KERN_INFO, sdev,
"%s: skip BDR, past eh deadline\n",
current->comm));
+ scsi_device_put(sdev);
break;
}
bdr_scmd = NULL;
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index be1a4a9a5fca..173bc7fc2836 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2859,8 +2859,10 @@ scsi_host_unblock(struct Scsi_Host *shost, int new_state)

shost_for_each_device(sdev, shost) {
ret = scsi_internal_device_unblock(sdev, new_state);
- if (ret)
+ if (ret) {
+ scsi_device_put(sdev);
break;
+ }
}
return ret;
}
--
2.21.3

2020-05-18 14:41:58

by Bart Van Assche

Subject: Re: [PATCH] scsi: Fix incorrect usage of shost_for_each_device

On 2020-05-18 00:44, Ye Bin wrote:
> shost_for_each_device(sdev, shost) \
> for ((sdev) = __scsi_iterate_devices((shost), NULL); \
> (sdev); \
> (sdev) = __scsi_iterate_devices((shost), (sdev)))
>
> When terminating shost_for_each_device() iteration with break or return,
> scsi_device_put() should be used to prevent stale scsi device references from
> being left behind.

Reviewed-by: Bart Van Assche <[email protected]>

2020-05-20 02:32:44

by Martin K. Petersen

Subject: Re: [PATCH] scsi: Fix incorrect usage of shost_for_each_device

On Mon, 18 May 2020 15:44:20 +0800, Ye Bin wrote:

> shost_for_each_device(sdev, shost) \
> for ((sdev) = __scsi_iterate_devices((shost), NULL); \
> (sdev); \
> (sdev) = __scsi_iterate_devices((shost), (sdev)))
>
> When terminating shost_for_each_device() iteration with break or return,
> scsi_device_put() should be used to prevent stale scsi device references from
> being left behind.

Applied to 5.8/scsi-queue, thanks!

[1/1] scsi: core: Fix incorrect usage of shost_for_each_device
https://git.kernel.org/mkp/scsi/c/4dea170f4fb2

--
Martin K. Petersen Oracle Linux Engineering

2020-06-04 06:08:31

by Hannes Reinecke

Subject: Re: [PATCH] scsi: Fix incorrect usage of shost_for_each_device

On 5/18/20 9:44 AM, Ye Bin wrote:
> shost_for_each_device(sdev, shost) \
> for ((sdev) = __scsi_iterate_devices((shost), NULL); \
> (sdev); \
> (sdev) = __scsi_iterate_devices((shost), (sdev)))
>
> When terminating shost_for_each_device() iteration with break or return,
> scsi_device_put() should be used to prevent stale scsi device references from
> being left behind.
>
> Signed-off-by: Ye Bin <[email protected]>
> ---
> drivers/scsi/scsi_error.c | 2 ++
> drivers/scsi/scsi_lib.c | 4 +++-
> 2 files changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
> index 978be1602f71..927b1e641842 100644
> --- a/drivers/scsi/scsi_error.c
> +++ b/drivers/scsi/scsi_error.c
> @@ -1412,6 +1412,7 @@ static int scsi_eh_stu(struct Scsi_Host *shost,
> sdev_printk(KERN_INFO, sdev,
> "%s: skip START_UNIT, past eh deadline\n",
> current->comm));
> + scsi_device_put(sdev);
> break;
> }
> stu_scmd = NULL;
> @@ -1478,6 +1479,7 @@ static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
> sdev_printk(KERN_INFO, sdev,
> "%s: skip BDR, past eh deadline\n",
> current->comm));
> + scsi_device_put(sdev);
> break;
> }
> bdr_scmd = NULL;
> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> index be1a4a9a5fca..173bc7fc2836 100644
> --- a/drivers/scsi/scsi_lib.c
> +++ b/drivers/scsi/scsi_lib.c
> @@ -2859,8 +2859,10 @@ scsi_host_unblock(struct Scsi_Host *shost, int new_state)
>
> shost_for_each_device(sdev, shost) {
> ret = scsi_internal_device_unblock(sdev, new_state);
> - if (ret)
> + if (ret) {
> + scsi_device_put(sdev);
> break;
> + }
> }
> return ret;
> }
>
Reviewed-by: Hannes Reinecke <[email protected]>

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
[email protected] +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer