From 62c789270c0b1ed5598c6b87c53b6908cd3c6eb5 Mon Sep 17 00:00:00 2001 From: Zqiang Date: Wed, 12 Aug 2020 16:55:01 +0800 Subject: [PATCH 1/2] libnvdimm: KASAN: global-out-of-bounds Read in internal_create_group Because the last member of the "nvdimm_firmware_attributes" array was not assigned a null ptr, when traversal of "grp->attrs" array is out of bounds in "create_files" func. func: create_files: ->for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) ->.... BUG: KASAN: global-out-of-bounds in create_files fs/sysfs/group.c:43 [inline] BUG: KASAN: global-out-of-bounds in internal_create_group+0x9d8/0xb20 fs/sysfs/group.c:149 Read of size 8 at addr ffffffff8a2e4cf0 by task kworker/u17:10/959 CPU: 2 PID: 959 Comm: kworker/u17:10 Not tainted 5.8.0-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 Workqueue: events_unbound async_run_entry_fn Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0x5/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 create_files fs/sysfs/group.c:43 [inline] internal_create_group+0x9d8/0xb20 fs/sysfs/group.c:149 internal_create_groups.part.0+0x90/0x140 fs/sysfs/group.c:189 internal_create_groups fs/sysfs/group.c:185 [inline] sysfs_create_groups+0x25/0x50 fs/sysfs/group.c:215 device_add_groups drivers/base/core.c:2024 [inline] device_add_attrs drivers/base/core.c:2178 [inline] device_add+0x7fd/0x1c40 drivers/base/core.c:2881 nd_async_device_register+0x12/0x80 drivers/nvdimm/bus.c:506 async_run_entry_fn+0x121/0x530 kernel/async.c:123 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 The buggy address belongs to the variable: nvdimm_firmware_attributes+0x10/0x40 Link: https://lore.kernel.org/r/20200812085501.30963-1-qiang.zhang@windriver.com Link: https://lore.kernel.org/r/20200814150509.225615-1-vaibhav@linux.ibm.com Fixes: 48001ea50d17f ("PM, libnvdimm: Add runtime firmware activation support") Reported-by: syzbot+1cf0ffe61aecf46f588f@syzkaller.appspotmail.com Reported-by: Sandipan Das Reported-by: Vaibhav Jain Reviewed-by: Ira Weiny Signed-off-by: Zqiang Signed-off-by: Vishal Verma --- drivers/nvdimm/dimm_devs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c index 61374def5155..b59032e0859b 100644 --- a/drivers/nvdimm/dimm_devs.c +++ b/drivers/nvdimm/dimm_devs.c @@ -529,6 +529,7 @@ static DEVICE_ATTR_ADMIN_RW(activate); static struct attribute *nvdimm_firmware_attributes[] = { &dev_attr_activate.attr, &dev_attr_result.attr, + NULL, }; static umode_t nvdimm_firmware_visible(struct kobject *kobj, struct attribute *a, int n) From c2affe920b0e0669650943ac086215cf6519be34 Mon Sep 17 00:00:00 2001 From: Adrian Huang Date: Wed, 19 Aug 2020 23:42:36 +0800 Subject: [PATCH 2/2] dax: do not print error message for non-persistent memory block device MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 231609785cbf ("dax: print error message by pr_info() in __generic_fsdax_supported()") happens to print the following error message during booting when the non-persistent memory block devices are configured by device mapper. Those error messages are caused by the variable 'dax_dev' is NULL. Users might be confused with those error messages since they do not use the persistent memory device. Moreover, users might scare about "what's wrong with my disks" because they see the 'error' and 'failed' keywords. # dmesg | grep fail sdk3: error: dax access failed (-95) sdk3: error: dax access failed (-95) sdk3: error: dax access failed (-95) sdk3: error: dax access failed (-95) sdk3: error: dax access failed (-95) sdk3: error: dax access failed (-95) sdk3: error: dax access failed (-95) sdk3: error: dax access failed (-95) sdk3: error: dax access failed (-95) sdb3: error: dax access failed (-95) sdb3: error: dax access failed (-95) sdb3: error: dax access failed (-95) sdb3: error: dax access failed (-95) sdb3: error: dax access failed (-95) sdb3: error: dax access failed (-95) sdb3: error: dax access failed (-95) sdb3: error: dax access failed (-95) sdb3: error: dax access failed (-95) # lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 1.1T 0 disk ├─sda1 8:1 0 156M 0 part ├─sda2 8:2 0 40G 0 part └─sda3 8:3 0 1.1T 0 part sdb 8:16 0 1.1T 0 disk ├─sdb1 8:17 0 600M 0 part ├─sdb2 8:18 0 1G 0 part └─sdb3 8:19 0 1.1T 0 part ├─rhel00-swap 254:3 0 4G 0 lvm ├─rhel00-home 254:4 0 1T 0 lvm └─rhel00-root 254:5 0 50G 0 lvm sdc 8:32 0 1.1T 0 disk sdd 8:48 0 1.1T 0 disk sde 8:64 0 1.1T 0 disk sdf 8:80 0 1.1T 0 disk sdg 8:96 0 1.1T 0 disk sdh 8:112 0 3.3T 0 disk ├─sdh1 8:113 0 500M 0 part /boot/efi ├─sdh2 8:114 0 40G 0 part / ├─sdh3 8:115 0 2.9T 0 part /home └─sdh4 8:116 0 314.6G 0 part [SWAP] sdi 8:128 0 1.1T 0 disk sdj 8:144 0 3.3T 0 disk ├─sdj1 8:145 0 512M 0 part └─sdj2 8:146 0 3.3T 0 part sdk 8:160 0 119.2G 0 disk ├─sdk1 8:161 0 200M 0 part ├─sdk2 8:162 0 1G 0 part └─sdk3 8:163 0 118G 0 part ├─rhel-swap 254:0 0 4G 0 lvm ├─rhel-home 254:1 0 64G 0 lvm └─rhel-root 254:2 0 50G 0 lvm sdl 8:176 0 119.2G 0 disk The call path is shown as follows: dm_table_determine_type dm_table_supports_dax device_supports_dax generic_fsdax_supported __generic_fsdax_supported With the disk configuration listing from the command 'lsblk', the member 'dev->dax_dev' of the block devices 'sdb3' and 'sdk3' (configured by device mapper) is NULL in function generic_fsdax_supported() because the member is configured in function open_table_device(). To prevent the confusing error messages in this scenario (this is normal behavior), just print those error messages by pr_debug() by checking if dax_dev is NULL and the block device does not support DAX. Link: https://lore.kernel.org/r/20200819154236.24191-1-adrianhuang0701@gmail.com Fixes: 231609785cbf ("dax: print error message by pr_info() in __generic_fsdax_supported()") Cc: Coly Li Cc: Dan Williams Cc: Alasdair Kergon Cc: Mike Snitzer Acked-by: Coly Li Signed-off-by: Adrian Huang Signed-off-by: Vishal Verma --- drivers/dax/super.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/dax/super.c b/drivers/dax/super.c index c82cbcb64202..32642634c1bb 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -100,6 +100,12 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev, return false; } + if (!dax_dev && !bdev_dax_supported(bdev, blocksize)) { + pr_debug("%s: error: dax unsupported by block device\n", + bdevname(bdev, buf)); + return false; + } + id = dax_read_lock(); len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn); len2 = dax_direct_access(dax_dev, pgoff_end, 1, &end_kaddr, &end_pfn);