diff options
| author | Jan Höppner <hoeppner@linux.ibm.com> | 2023-06-09 18:37:50 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-06-14 12:15:27 +0300 |
| commit | 1e1e2ee0cf7fae4d69583a86111e720ff9637ee7 (patch) | |
| tree | 030497d909e49842651b46abd18c7a6a46763415 | |
| parent | 6f5c0eec89fc6f0c8ee6e8de8a72b7280837534f (diff) | |
| download | linux-1e1e2ee0cf7fae4d69583a86111e720ff9637ee7.tar.xz | |
s390/dasd: Use correct lock while counting channel queue length
commit ccc45cb4e7271c74dbb27776ae8f73d84557f5c6 upstream.
The lock around counting the channel queue length in the BIODASDINFO
ioctl was incorrectly changed to the dasd_block->queue_lock with commit
583d6535cb9d ("dasd: remove dead code"). This can lead to endless list
iterations and a subsequent crash.
The queue_lock is supposed to be used only for queue lists belonging to
dasd_block. For dasd_device related queue lists the ccwdev lock must be
used.
Fix the mentioned issues by correctly using the ccwdev lock instead of
the queue lock.
Fixes: 583d6535cb9d ("dasd: remove dead code")
Cc: stable@vger.kernel.org # v5.0+
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20230609153750.1258763-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/s390/block/dasd_ioctl.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c index 9327dcdd6e5e..8fca725b3dae 100644 --- a/drivers/s390/block/dasd_ioctl.c +++ b/drivers/s390/block/dasd_ioctl.c @@ -552,10 +552,10 @@ static int __dasd_ioctl_information(struct dasd_block *block, memcpy(dasd_info->type, base->discipline->name, 4); - spin_lock_irqsave(&block->queue_lock, flags); + spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags); list_for_each(l, &base->ccw_queue) dasd_info->chanq_len++; - spin_unlock_irqrestore(&block->queue_lock, flags); + spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags); return 0; } |