diff options
| author | Coly Li <colyli@suse.de> | 2020-07-25 20:00:21 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-07-25 07:38:20 -0600 |
| commit | 65f0f017e7be8c70330372df23bcb2a407ecf02d (patch) | |
| tree | 045f0bed9e860961cc83ef9b2cd821a9ba35de13 /drivers/md | |
| parent | 29f1d5caced9c2db96f169422bade787ff45d584 (diff) | |
bcache: avoid nr_stripes overflow in bcache_device_init()
For some block devices which large capacity (e.g. 8TB) but small io_opt
size (e.g. 8 sectors), in bcache_device_init() the stripes number calcu-
lated by,
DIV_ROUND_UP_ULL(sectors, d->stripe_size);
might be overflow to the unsigned int bcache_device->nr_stripes.
This patch uses the uint64_t variable to store DIV_ROUND_UP_ULL()
and after the value is checked to be available in unsigned int range,
sets it to bache_device->nr_stripes. Then the overflow is avoided.
Reported-and-tested-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1783075
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/bcache/super.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 4a77bfd4009f..0f90616dc8d3 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -835,19 +835,19 @@ static int bcache_device_init(struct bcache_device *d, unsigned int block_size, struct request_queue *q; const size_t max_stripes = min_t(size_t, INT_MAX, SIZE_MAX / sizeof(atomic_t)); - size_t n; + uint64_t n; int idx; if (!d->stripe_size) d->stripe_size = 1 << 31; - d->nr_stripes = DIV_ROUND_UP_ULL(sectors, d->stripe_size); - - if (!d->nr_stripes || d->nr_stripes > max_stripes) { - pr_err("nr_stripes too large or invalid: %u (start sector beyond end of disk?)\n", - (unsigned int)d->nr_stripes); + n = DIV_ROUND_UP_ULL(sectors, d->stripe_size); + if (!n || n > max_stripes) { + pr_err("nr_stripes too large or invalid: %llu (start sector beyond end of disk?)\n", + n); return -ENOMEM; } + d->nr_stripes = n; n = d->nr_stripes * sizeof(atomic_t); d->stripe_sectors_dirty = kvzalloc(n, GFP_KERNEL); |