ext4: aovid use-after-free in ext4_ext_insert_extent()
As Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is
reallocated in ext4_ext_create_new_leaf(), we'll use the stale path and
cause UAF. Below is a sample trace with dummy values:
ext4_ext_insert_extent
path = *ppath = 2000
ext4_ext_create_new_leaf(ppath)
ext4_find_extent(ppath)
path = *ppath = 2000
if (depth > path[0].p_maxdepth)
kfree(path = 2000);
*ppath = path = NULL;
path = kcalloc() = 3000
*ppath = 3000;
return path;
/* here path is still 2000, UAF! */
eh = path[depth].p_hdr
==================================================================
BUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330
Read of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179
CPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866
Call Trace:
<TASK>
ext4_ext_insert_extent+0x26d4/0x3330
ext4_ext_map_blocks+0xe22/0x2d40
ext4_map_blocks+0x71e/0x1700
ext4_do_writepages+0x1290/0x2800
[...]
Allocated by task 179:
ext4_find_extent+0x81c/0x1f70
ext4_ext_map_blocks+0x146/0x2d40
ext4_map_blocks+0x71e/0x1700
ext4_do_writepages+0x1290/0x2800
ext4_writepages+0x26d/0x4e0
do_writepages+0x175/0x700
[...]
Freed by task 179:
kfree+0xcb/0x240
ext4_find_extent+0x7c0/0x1f70
ext4_ext_insert_extent+0xa26/0x3330
ext4_ext_map_blocks+0xe22/0x2d40
ext4_map_blocks+0x71e/0x1700
ext4_do_writepages+0x1290/0x2800
ext4_writepages+0x26d/0x4e0
do_writepages+0x175/0x700
[...]
==================================================================
So use *ppath to update the path to avoid the above problem.
Metrics
Affected Vendors & Products
| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-4008-1 | linux-6.1 security update |
Debian DLA |
DLA-4075-1 | linux security update |
Ubuntu USN |
USN-7166-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7166-2 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7166-3 | Linux kernel (HWE) vulnerabilities |
Ubuntu USN |
USN-7166-4 | Linux kernel (Xilinx ZynqMP) vulnerabilities |
Ubuntu USN |
USN-7186-1 | Linux kernel (Intel IoTG) vulnerabilities |
Ubuntu USN |
USN-7186-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7194-1 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-7276-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7277-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7293-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7294-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7294-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7294-3 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7294-4 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7295-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7301-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7303-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7303-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7303-3 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7304-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7310-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7311-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7384-1 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-7384-2 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-7385-1 | Linux kernel (IBM) vulnerabilities |
Ubuntu USN |
USN-7386-1 | Linux kernel (OEM) vulnerabilities |
Ubuntu USN |
USN-7393-1 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7401-1 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7403-1 | Linux kernel (HWE) vulnerabilities |
Ubuntu USN |
USN-7413-1 | Linux kernel (IoT) vulnerabilities |
Ubuntu USN |
USN-7468-1 | Linux kernel (Azure, N-Series) vulnerabilities |
Ubuntu USN |
USN-7539-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-7540-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-7684-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7684-2 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7684-3 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7685-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7685-2 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-7685-3 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7685-4 | Linux kernel (Oracle) vulnerabilities |
Ubuntu USN |
USN-7685-5 | Linux kernel (Oracle) vulnerabilities |
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Mon, 03 Nov 2025 23:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Mon, 03 Nov 2025 21:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Wed, 14 May 2025 02:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Redhat
Redhat enterprise Linux |
|
| CPEs | cpe:/a:redhat:enterprise_linux:9 cpe:/o:redhat:enterprise_linux:9 |
|
| Vendors & Products |
Redhat
Redhat enterprise Linux |
Fri, 08 Nov 2024 16:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Fri, 25 Oct 2024 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| Weaknesses | CWE-416 | |
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| Metrics |
cvssV3_1
|
cvssV3_1
|
Wed, 23 Oct 2024 01:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Tue, 22 Oct 2024 14:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Mon, 21 Oct 2024 18:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: ext4: aovid use-after-free in ext4_ext_insert_extent() As Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is reallocated in ext4_ext_create_new_leaf(), we'll use the stale path and cause UAF. Below is a sample trace with dummy values: ext4_ext_insert_extent path = *ppath = 2000 ext4_ext_create_new_leaf(ppath) ext4_find_extent(ppath) path = *ppath = 2000 if (depth > path[0].p_maxdepth) kfree(path = 2000); *ppath = path = NULL; path = kcalloc() = 3000 *ppath = 3000; return path; /* here path is still 2000, UAF! */ eh = path[depth].p_hdr ================================================================== BUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330 Read of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179 CPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866 Call Trace: <TASK> ext4_ext_insert_extent+0x26d4/0x3330 ext4_ext_map_blocks+0xe22/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 [...] Allocated by task 179: ext4_find_extent+0x81c/0x1f70 ext4_ext_map_blocks+0x146/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 ext4_writepages+0x26d/0x4e0 do_writepages+0x175/0x700 [...] Freed by task 179: kfree+0xcb/0x240 ext4_find_extent+0x7c0/0x1f70 ext4_ext_insert_extent+0xa26/0x3330 ext4_ext_map_blocks+0xe22/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 ext4_writepages+0x26d/0x4e0 do_writepages+0x175/0x700 [...] ================================================================== So use *ppath to update the path to avoid the above problem. | |
| Title | ext4: aovid use-after-free in ext4_ext_insert_extent() | |
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-11-03T22:22:49.557Z
Reserved: 2024-10-21T12:17:06.021Z
Link: CVE-2024-49883
Updated: 2025-11-03T22:22:49.557Z
Status : Modified
Published: 2024-10-21T18:15:11.060
Modified: 2025-11-03T23:16:28.533
Link: CVE-2024-49883
OpenCVE Enrichment
No data.
Debian DLA
Ubuntu USN