CVE-2024-49881

Nov. 8, 2024, 4:15 p.m.

5.5
Medium

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: update orig_path in ext4_find_extent() In ext4_find_extent(), if the path is not big enough, we free it and set *orig_path to NULL. But after reallocating and successfully initializing the path, we don't update *orig_path, in which case the caller gets a valid path but a NULL ppath, and this may cause a NULL pointer dereference or a path memory leak. For example: ext4_split_extent path = *ppath = 2000 ext4_find_extent if (depth > path[0].p_maxdepth) kfree(path = 2000); *orig_path = path = NULL; path = kcalloc() = 3000 ext4_split_extent_at(*ppath = NULL) path = *ppath; ex = path[depth].p_ext; // NULL pointer dereference! ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000010 CPU: 6 UID: 0 PID: 576 Comm: fsstress Not tainted 6.11.0-rc2-dirty #847 RIP: 0010:ext4_split_extent_at+0x6d/0x560 Call Trace: <TASK> ext4_split_extent.isra.0+0xcb/0x1b0 ext4_ext_convert_to_initialized+0x168/0x6c0 ext4_ext_handle_unwritten_extents+0x325/0x4d0 ext4_ext_map_blocks+0x520/0xdb0 ext4_map_blocks+0x2b0/0x690 ext4_iomap_begin+0x20e/0x2c0 [...] ================================================================== Therefore, *orig_path is updated when the extent lookup succeeds, so that the caller can safely use path or *ppath.

Product(s) Impacted

Vendor Product Versions
Linux
  • Linux Kernel
  • *

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-476
NULL Pointer Dereference
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
o linux linux_kernel / / / / / / / /
o linux linux_kernel / / / / / / / /
o linux linux_kernel / / / / / / / /
o linux linux_kernel / / / / / / / /
o linux linux_kernel / / / / / / / /
o linux linux_kernel / / / / / / / /

References

https://git.kernel.org/stable/c/11b230100d6801c014fab2afabc8bdea304c1b96
https://git.kernel.org/stable/c/5b4b2dcace35f618fe361a87bae6f0d13af31bc1
https://git.kernel.org/stable/c/6766937d0327000ac1b87c97bbecdd28b0dd6599
https://git.kernel.org/stable/c/6801ed1298204d16a38571091e31178bfdc3c679
https://git.kernel.org/stable/c/a9fcb1717d75061d3653ed69365c8d45331815cd
https://git.kernel.org/stable/c/b63481b3a388ee2df9e295f97273226140422a42
https://git.kernel.org/stable/c/ec0c0beb9b777cdd1edd7df9b36e0f3e67e2bdff
https://git.kernel.org/stable/c/f55ecc58d07a6c1f6d6d5b5af125c25f8da0bda2

Tags

416baaa9-dc9f-4396-8d5f-8c081fb06d67
CWE-476
2024-10-21
CVE-2024-49881

CVSS Score

5.5 / 10

CVSS Data - 3.1

  • Attack Vector: LOCAL
  • Attack Complexity: LOW
  • Privileges Required: LOW
  • Scope: UNCHANGED
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: HIGH

    • CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

    View Vector String

Timeline

Published: Oct. 21, 2024, 6:15 p.m.
Last Modified: Nov. 8, 2024, 4:15 p.m.

Status : Modified

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

416baaa9-dc9f-4396-8d5f-8c081fb06d67

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.