diff options
| author | Chen Jun <chenjun102@huawei.com> | 2022-11-16 04:27:14 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-11 18:40:11 +0300 |
| commit | c5a21a5501508ae3afa2fe6d5a3e74a37fa48df3 (patch) | |
| tree | fa5f81b7eecaf66c6dbeb0898333421d768aac3e /drivers | |
| parent | 273559f58f71512e4be929b78d4e05f60d48a60c (diff) | |
| download | linux-c5a21a5501508ae3afa2fe6d5a3e74a37fa48df3.tar.xz | |
watchdog: Fix kmemleak in watchdog_cdev_register
[ Upstream commit 13721a2ac66b246f5802ba1b75ad8637e53eeecc ]
kmemleak reports memory leaks in watchdog_dev_register, as follows:
unreferenced object 0xffff888116233000 (size 2048):
comm ""modprobe"", pid 28147, jiffies 4353426116 (age 61.741s)
hex dump (first 32 bytes):
80 fa b9 05 81 88 ff ff 08 30 23 16 81 88 ff ff .........0#.....
08 30 23 16 81 88 ff ff 00 00 00 00 00 00 00 00 .0#.............
backtrace:
[<000000007f001ffd>] __kmem_cache_alloc_node+0x157/0x220
[<000000006a389304>] kmalloc_trace+0x21/0x110
[<000000008d640eea>] watchdog_dev_register+0x4e/0x780 [watchdog]
[<0000000053c9f248>] __watchdog_register_device+0x4f0/0x680 [watchdog]
[<00000000b2979824>] watchdog_register_device+0xd2/0x110 [watchdog]
[<000000001f730178>] 0xffffffffc10880ae
[<000000007a1a8bcc>] do_one_initcall+0xcb/0x4d0
[<00000000b98be325>] do_init_module+0x1ca/0x5f0
[<0000000046d08e7c>] load_module+0x6133/0x70f0
...
unreferenced object 0xffff888105b9fa80 (size 16):
comm ""modprobe"", pid 28147, jiffies 4353426116 (age 61.741s)
hex dump (first 16 bytes):
77 61 74 63 68 64 6f 67 31 00 b9 05 81 88 ff ff watchdog1.......
backtrace:
[<000000007f001ffd>] __kmem_cache_alloc_node+0x157/0x220
[<00000000486ab89b>] __kmalloc_node_track_caller+0x44/0x1b0
[<000000005a39aab0>] kvasprintf+0xb5/0x140
[<0000000024806f85>] kvasprintf_const+0x55/0x180
[<000000009276cb7f>] kobject_set_name_vargs+0x56/0x150
[<00000000a92e820b>] dev_set_name+0xab/0xe0
[<00000000cec812c6>] watchdog_dev_register+0x285/0x780 [watchdog]
[<0000000053c9f248>] __watchdog_register_device+0x4f0/0x680 [watchdog]
[<00000000b2979824>] watchdog_register_device+0xd2/0x110 [watchdog]
[<000000001f730178>] 0xffffffffc10880ae
[<000000007a1a8bcc>] do_one_initcall+0xcb/0x4d0
[<00000000b98be325>] do_init_module+0x1ca/0x5f0
[<0000000046d08e7c>] load_module+0x6133/0x70f0
...
The reason is that put_device is not be called if cdev_device_add fails
and wdd->id != 0.
watchdog_cdev_register
wd_data = kzalloc [1]
err = dev_set_name [2]
..
err = cdev_device_add
if (err) {
if (wdd->id == 0) { // wdd->id != 0
..
}
return err; // [1],[2] would be leaked
To fix it, call put_device in all wdd->id cases.
Fixes: 72139dfa2464 ("watchdog: Fix the race between the release of watchdog_core_data and cdev")
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20221116012714.102066-1-chenjun102@huawei.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/watchdog/watchdog_dev.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 2ee017442dfc..f37255cd75fd 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -1037,8 +1037,8 @@ static int watchdog_cdev_register(struct watchdog_device *wdd) if (wdd->id == 0) { misc_deregister(&watchdog_miscdev); old_wd_data = NULL; - put_device(&wd_data->dev); } + put_device(&wd_data->dev); return err; } |