diff options
| author | Ziyang Xuan <william.xuanziyang@huawei.com> | 2021-10-15 10:45:04 +0800 |
|---|---|---|
| committer | Daniel Lezcano <daniel.lezcano@linaro.org> | 2021-10-15 15:38:48 +0200 |
| commit | 0a5c26712f963f0500161a23e0ffff8d29f742ab (patch) | |
| tree | d04671d4e759a112f66b5927e093301e9102b3c0 /drivers/thermal | |
| parent | 1dd7128b839f631b31a9e9dce3aaf639bef74e9d (diff) | |
thermal/core: fix a UAF bug in __thermal_cooling_device_register()
When device_register() return failed, program will goto out_kfree_type
to release 'cdev->device' by put_device(). That will call thermal_release()
to free 'cdev'. But the follow-up processes access 'cdev' continually.
That trggers the UAF bug.
====================================================================
BUG: KASAN: use-after-free in __thermal_cooling_device_register+0x75b/0xa90
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
dump_stack_lvl+0xe2/0x152
print_address_description.constprop.0+0x21/0x140
? __thermal_cooling_device_register+0x75b/0xa90
kasan_report.cold+0x7f/0x11b
? __thermal_cooling_device_register+0x75b/0xa90
__thermal_cooling_device_register+0x75b/0xa90
? memset+0x20/0x40
? __sanitizer_cov_trace_pc+0x1d/0x50
? __devres_alloc_node+0x130/0x180
devm_thermal_of_cooling_device_register+0x67/0xf0
max6650_probe.cold+0x557/0x6aa
......
Freed by task 258:
kasan_save_stack+0x1b/0x40
kasan_set_track+0x1c/0x30
kasan_set_free_info+0x20/0x30
__kasan_slab_free+0x109/0x140
kfree+0x117/0x4c0
thermal_release+0xa0/0x110
device_release+0xa7/0x240
kobject_put+0x1ce/0x540
put_device+0x20/0x30
__thermal_cooling_device_register+0x731/0xa90
devm_thermal_of_cooling_device_register+0x67/0xf0
max6650_probe.cold+0x557/0x6aa [max6650]
Do not use 'cdev' again after put_device() to fix the problem like doing
in thermal_zone_device_register().
[dlezcano]: as requested by Rafael, change the affectation into two statements.
Fixes: 584837618100 ("thermal/drivers/core: Use a char pointer for the cooling device name")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20211015024504.947520-1-william.xuanziyang@huawei.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Diffstat (limited to 'drivers/thermal')
| -rw-r--r-- | drivers/thermal/thermal_core.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 6904b97fd6ea..648829ab79ff 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -889,7 +889,7 @@ __thermal_cooling_device_register(struct device_node *np, { struct thermal_cooling_device *cdev; struct thermal_zone_device *pos = NULL; - int ret; + int id, ret; if (!ops || !ops->get_max_state || !ops->get_cur_state || !ops->set_cur_state) @@ -903,6 +903,7 @@ __thermal_cooling_device_register(struct device_node *np, if (ret < 0) goto out_kfree_cdev; cdev->id = ret; + id = ret; ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id); if (ret) @@ -946,8 +947,9 @@ __thermal_cooling_device_register(struct device_node *np, out_kfree_type: kfree(cdev->type); put_device(&cdev->device); + cdev = NULL; out_ida_remove: - ida_simple_remove(&thermal_cdev_ida, cdev->id); + ida_simple_remove(&thermal_cdev_ida, id); out_kfree_cdev: kfree(cdev); return ERR_PTR(ret); |