In the Linux kernel, the following vulnerability has been resolved:
ext4: fix mb_cache_entry's e_refcnt leak in ext4_xattr_block_cache_find()
Syzbot reports a warning as follows:
============================================
WARNING: CPU: 0 PID: 5075 at fs/mbcache.c:419 mb_cache_destroy+0x224/0x290
Modules linked in:
CPU: 0 PID: 5075 Comm: syz-executor199 Not tainted 6.9.0-rc6-gb947cc5bf6d7
RIP: 0010:mb_cache_destroy+0x224/0x290 fs/mbcache.c:419
Call Trace:
<TASK>
ext4_put_super+0x6d4/0xcd0 fs/ext4/super.c:1375
generic_shutdown_super+0x136/0x2d0 fs/super.c:641
kill_block_super+0x44/0x90 fs/super.c:1675
ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7327
[...]
============================================
This is because when finding an entry in ext4_xattr_block_cache_find(), if
ext4_sb_bread() returns -ENOMEM, the ce's e_refcnt, which has already grown
in the __entry_find(), won't be put away, and eventually trigger the above
issue in mb_cache_destroy() due to reference count leakage.
So call mb_cache_entry_put() on the -ENOMEM error branch as a quick fix.
ext4: fix mb_cache_entry's e_refcnt leak in ext4_xattr_block_cache_find()
Syzbot reports a warning as follows:
============================================
WARNING: CPU: 0 PID: 5075 at fs/mbcache.c:419 mb_cache_destroy+0x224/0x290
Modules linked in:
CPU: 0 PID: 5075 Comm: syz-executor199 Not tainted 6.9.0-rc6-gb947cc5bf6d7
RIP: 0010:mb_cache_destroy+0x224/0x290 fs/mbcache.c:419
Call Trace:
<TASK>
ext4_put_super+0x6d4/0xcd0 fs/ext4/super.c:1375
generic_shutdown_super+0x136/0x2d0 fs/super.c:641
kill_block_super+0x44/0x90 fs/super.c:1675
ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7327
[...]
============================================
This is because when finding an entry in ext4_xattr_block_cache_find(), if
ext4_sb_bread() returns -ENOMEM, the ce's e_refcnt, which has already grown
in the __entry_find(), won't be put away, and eventually trigger the above
issue in mb_cache_destroy() due to reference count leakage.
So call mb_cache_entry_put() on the -ENOMEM error branch as a quick fix.
Metrics
Affected Vendors & Products
Advisories
| Source | ID | Title |
|---|---|---|
Debian DSA |
DSA-5730-1 | linux security update |
Ubuntu USN |
USN-6951-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-6951-2 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-6951-3 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-6951-4 | Linux kernel (BlueField) vulnerabilities |
Ubuntu USN |
USN-6953-1 | Linux kernel (Oracle) vulnerabilities |
Ubuntu USN |
USN-6979-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-6999-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-6999-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7004-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7005-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7005-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7007-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7007-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7007-3 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7008-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7009-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7009-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7019-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7029-1 | Linux kernel vulnerabilities |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Mon, 24 Mar 2025 17:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| Weaknesses | NVD-CWE-Other | |
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
Wed, 05 Mar 2025 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Redhat rhel Eus
|
|
| CPEs | cpe:/a:redhat:rhel_eus:9.4 | |
| Vendors & Products |
Redhat rhel Eus
|
Wed, 13 Nov 2024 02:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| CPEs | cpe:/a:redhat:enterprise_linux:9 cpe:/o:redhat:enterprise_linux:9 |
Thu, 08 Aug 2024 23:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Redhat
Redhat enterprise Linux |
|
| CPEs | cpe:/a:redhat:enterprise_linux:8::nfv cpe:/o:redhat:enterprise_linux:8 |
|
| Vendors & Products |
Redhat
Redhat enterprise Linux |
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-05-04T12:56:59.037Z
Reserved: 2024-06-24T13:53:25.552Z
Link: CVE-2024-39276
Updated: 2024-08-02T04:19:20.631Z
Status : Analyzed
Published: 2024-06-25T15:15:13.903
Modified: 2025-03-24T17:28:00.347
Link: CVE-2024-39276
OpenCVE Enrichment
No data.
Debian DSA
Ubuntu USN