diff options
| author | Uday Shankar <ushankar@purestorage.com> | 2022-09-24 03:02:42 +0300 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2022-10-18 05:26:29 +0300 |
| commit | 2331ce6126be8864b39490e705286b66e2344aac (patch) | |
| tree | 2622c427146c4e2d39fa3425884aaa447ad843c8 | |
| parent | 9abf2313adc1ca1b6180c508c25f22f9395cc780 (diff) | |
| download | linux-2331ce6126be8864b39490e705286b66e2344aac.tar.xz | |
scsi: core: Restrict legal sdev_state transitions via sysfs
Userspace can currently write to sysfs to transition sdev_state to RUNNING
or OFFLINE from any source state. This causes issues because proper
transitioning out of some states involves steps besides just changing
sdev_state, so allowing userspace to change sdev_state regardless of the
source state can result in inconsistencies; e.g. with ISCSI we can end up
with sdev_state == SDEV_RUNNING while the device queue is quiesced. Any
task attempting I/O on the device will then hang, and in more recent
kernels, iscsid will hang as well.
More detail about this bug is provided in my first attempt:
https://groups.google.com/g/open-iscsi/c/PNKca4HgPDs/m/CXaDkntOAQAJ
Link: https://lore.kernel.org/r/20220924000241.2967323-1-ushankar@purestorage.com
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Suggested-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| -rw-r--r-- | drivers/scsi/scsi_sysfs.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index c95177ca6ed2..cac7c902cf70 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -828,6 +828,14 @@ store_state_field(struct device *dev, struct device_attribute *attr, } mutex_lock(&sdev->state_mutex); + switch (sdev->sdev_state) { + case SDEV_RUNNING: + case SDEV_OFFLINE: + break; + default: + mutex_unlock(&sdev->state_mutex); + return -EINVAL; + } if (sdev->sdev_state == SDEV_RUNNING && state == SDEV_RUNNING) { ret = 0; } else { |