ext4: fix uninitialized ratelimit_state->lock access in __ext4_fill_super()
In the following concurrency we will access the uninitialized rs->lock:
ext4_fill_super
ext4_register_sysfs
// sysfs registered msg_ratelimit_interval_ms
// Other processes modify rs->interval to
// non-zero via msg_ratelimit_interval_ms
ext4_orphan_cleanup
ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
__ext4_msg
___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state)
if (!rs->interval) // do nothing if interval is 0
return 1;
raw_spin_trylock_irqsave(&rs->lock, flags)
raw_spin_trylock(lock)
_raw_spin_trylock
__raw_spin_trylock
spin_acquire(&lock->dep_map, 0, 1, _RET_IP_)
lock_acquire
__lock_acquire
register_lock_class
assign_lock_key
dump_stack();
ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
raw_spin_lock_init(&rs->lock);
// init rs->lock here
and get the following dump_stack:
=========================================================
INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 12 PID: 753 Comm: mount Tainted: G E 6.7.0-rc6-next-20231222 #504
[...]
Call Trace:
dump_stack_lvl+0xc5/0x170
dump_stack+0x18/0x30
register_lock_class+0x740/0x7c0
__lock_acquire+0x69/0x13a0
lock_acquire+0x120/0x450
_raw_spin_trylock+0x98/0xd0
___ratelimit+0xf6/0x220
__ext4_msg+0x7f/0x160 [ext4]
ext4_orphan_cleanup+0x665/0x740 [ext4]
__ext4_fill_super+0x21ea/0x2b10 [ext4]
ext4_fill_super+0x14d/0x360 [ext4]
[...]
=========================================================
Normally interval is 0 until s_msg_ratelimit_state is initialized, so
___ratelimit() does nothing. But registering sysfs precedes initializing
rs->lock, so it is possible to change rs->interval to a non-zero value
via the msg_ratelimit_interval_ms interface of sysfs while rs->lock is
uninitialized, and then a call to ext4_msg triggers the problem by
accessing an uninitialized rs->lock. Therefore register sysfs after all
initializations are complete to avoid such problems.
Metrics
Affected Vendors & Products
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Wed, 06 Nov 2024 08:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Metrics |
ssvc
|
Wed, 30 Oct 2024 15:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Redhat rhel Aus
Redhat rhel E4s Redhat rhel Tus |
|
CPEs | cpe:/a:redhat:enterprise_linux:9 cpe:/a:redhat:rhel_eus:9.2 cpe:/a:redhat:rhel_eus:9.2::nfv cpe:/o:redhat:enterprise_linux:9 cpe:/o:redhat:rhel_aus:8.6 cpe:/o:redhat:rhel_e4s:8.6 cpe:/o:redhat:rhel_tus:8.6 |
|
Vendors & Products |
Redhat rhel Aus
Redhat rhel E4s Redhat rhel Tus |
Wed, 16 Oct 2024 02:30:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Redhat rhel Eus
|
|
CPEs | cpe:/o:redhat:rhel_eus:8.8 | |
Vendors & Products |
Redhat rhel Eus
|
Tue, 24 Sep 2024 11:00:00 +0000
Type | Values Removed | Values Added |
---|---|---|
CPEs | cpe:/o:redhat:enterprise_linux:8 |
Tue, 24 Sep 2024 06:30:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Redhat
Redhat enterprise Linux |
|
CPEs | cpe:/a:redhat:enterprise_linux:8::nfv | |
Vendors & Products |
Redhat
Redhat enterprise Linux |
Thu, 12 Sep 2024 08:30:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Metrics |
ssvc
|
Wed, 11 Sep 2024 13:30:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Metrics |
ssvc
|

Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-05-04T09:19:40.394Z
Reserved: 2024-07-12T12:17:45.607Z
Link: CVE-2024-40998

Updated: 2024-08-02T04:39:56.156Z

Status : Awaiting Analysis
Published: 2024-07-12T13:15:20.857
Modified: 2024-11-21T09:32:02.043
Link: CVE-2024-40998


No data.