From: Khazhismel Kumykov <khazhy@google.com>
Date: Thu, 14 Apr 2022 15:40:56 -0700
Subject: [PATCH] block/compat_ioctl: fix range check in BLKGETSIZE
Git-commit: ccf16413e520164eb718cf8b22a30438da80ff23
Patch-mainline: v5.18-rc3
References: jsc#PED-1183
kernel ulong and compat_ulong_t may not be same width. Use type directly
to eliminate mismatches.
This would result in truncation rather than EFBIG for 32bit mode for
large disks.
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220414224056.2875681-1-khazhy@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
block/ioctl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/ioctl.c b/block/ioctl.c
index 4a86340133e4..f8703db99c73 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -629,7 +629,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
return compat_put_long(argp,
(bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
case BLKGETSIZE:
- if (bdev_nr_sectors(bdev) > ~0UL)
+ if (bdev_nr_sectors(bdev) > ~(compat_ulong_t)0)
return -EFBIG;
return compat_put_ulong(argp, bdev_nr_sectors(bdev));
--
2.35.3