From: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx> [ Upstream commit e274832590211c4b1b1e807ca66fad8b5bb8b328 ] In null_init_zone_dev() check if the zone size is larger than device capacity, return error if needed. This also fixes the following oops :- null_blk: changed the number of conventional zones to 4294967295 BUG: kernel NULL pointer dereference, address: 0000000000000010 PGD 7d76c5067 P4D 7d76c5067 PUD 7d240c067 PMD 0 Oops: 0002 [#1] SMP NOPTI CPU: 4 PID: 5508 Comm: nullbtests.sh Tainted: G OE 5.7.0-rc4lblk-fnext0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e4 RIP: 0010:null_init_zoned_dev+0x17a/0x27f [null_blk] RSP: 0018:ffffc90007007e00 EFLAGS: 00010246 RAX: 0000000000000020 RBX: ffff8887fb3f3c00 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffff8887ca09d688 RDI: ffff888810fea510 RBP: 0000000000000010 R08: ffff8887ca09d688 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8887c26e8000 R13: ffffffffa05e9390 R14: 0000000000000000 R15: 0000000000000001 FS: 00007fcb5256f740(0000) GS:ffff888810e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 000000081e8fe000 CR4: 00000000003406e0 Call Trace: null_add_dev+0x534/0x71b [null_blk] nullb_device_power_store.cold.41+0x8/0x2e [null_blk] configfs_write_file+0xe6/0x150 vfs_write+0xba/0x1e0 ksys_write+0x5f/0xe0 do_syscall_64+0x60/0x250 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x7fcb51c71840 Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/block/null_blk_zoned.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c index ed34785dd64b..5dc955f5ea0a 100644 --- a/drivers/block/null_blk_zoned.c +++ b/drivers/block/null_blk_zoned.c @@ -20,6 +20,10 @@ int null_zone_init(struct nullb_device *dev) pr_err("zone_size must be power-of-two\n"); return -EINVAL; } + if (dev->zone_size > dev->size) { + pr_err("Zone size larger than device capacity\n"); + return -EINVAL; + } dev->zone_size_sects = dev->zone_size << ZONE_SIZE_SHIFT; dev->nr_zones = dev_size >> -- 2.25.1