diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2025-12-01 16:43:26 -0500 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-12-04 07:19:26 -0700 |
| commit | ab4fb1d8f6e98575703474491538febff6b1a2c9 (patch) | |
| tree | 832c38b257f2e31410af3a8f331fb1e78415c056 /drivers/scsi | |
| parent | 48f22f80938d94c34319f90674de6102ca37eabc (diff) | |
scsi: sd: reject invalid pr_read_keys() num_keys values
The pr_read_keys() interface has a u32 num_keys parameter. The SCSI
PERSISTENT RESERVE IN command has a maximum READ KEYS service action
size of 65536 bytes. Reject num_keys values that are too large to fit
into the SCSI command.
This will become important when pr_read_keys() is exposed to untrusted
userspace via an <linux/pr.h> ioctl.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/sd.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 0252d3f6bed1..32ae4898cea7 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1974,9 +1974,19 @@ static int sd_pr_read_keys(struct block_device *bdev, struct pr_keys *keys_info) { int result, i, data_offset, num_copy_keys; u32 num_keys = keys_info->num_keys; - int data_len = num_keys * 8 + 8; + int data_len; u8 *data; + /* + * Each reservation key takes 8 bytes and there is an 8-byte header + * before the reservation key list. The total size must fit into the + * 16-bit ALLOCATION LENGTH field. + */ + if (check_mul_overflow(num_keys, 8, &data_len) || + check_add_overflow(data_len, 8, &data_len) || + data_len > USHRT_MAX) + return -EINVAL; + data = kzalloc(data_len, GFP_KERNEL); if (!data) return -ENOMEM; |