CVE-2024-49881

CVE Details

Release Date:

2024-10-21

Description

In the Linux kernel, the following vulnerability has been resolved:\next4: update orig_path in ext4_find_extent()\nIn ext4_find_extent(), if the path is not big enough, we free it and set\n*orig_path to NULL. But after reallocating and successfully initializing\nthe path, we don't update *orig_path, in which case the caller gets a\nvalid path but a NULL ppath, and this may cause a NULL pointer dereference\nor a path memory leak. For example:\next4_split_extent\npath = *ppath = 2000\next4_find_extent\nif (depth > path[0].p_maxdepth)\nkfree(path = 2000);\n*orig_path = path = NULL;\npath = kcalloc() = 3000\next4_split_extent_at(*ppath = NULL)\npath = *ppath;\nex = path[depth].p_ext;\n// NULL pointer dereference!\n==================================================================\nBUG: kernel NULL pointer dereference, address: 0000000000000010\nCPU: 6 UID: 0 PID: 576 Comm: fsstress Not tainted 6.11.0-rc2-dirty #847\nRIP: 0010:ext4_split_extent_at+0x6d/0x560\nCall Trace:\n\next4_split_extent.isra.0+0xcb/0x1b0\next4_ext_convert_to_initialized+0x168/0x6c0\next4_ext_handle_unwritten_extents+0x325/0x4d0\next4_ext_map_blocks+0x520/0xdb0\next4_map_blocks+0x2b0/0x690\next4_iomap_begin+0x20e/0x2c0\n[...]\n==================================================================\nTherefore, *orig_path is updated when the extent lookup succeeds, so that\nthe caller can safely use path or *ppath.

See more information about CVE-2024-49881 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	5.5
Vector String:	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Version:	3.1
Attack Vector:	Local
Attack Complexity:	Low
Privileges Required:	Low
User Interaction:	None
Scope:	Unchanged
Confidentiality:	None
Integrity:	None
Availability:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 8 (kernel-uek)	ELSA-2024-12887	2024-12-18
Oracle Linux version 9 (kernel-uek)	ELSA-2024-12887	2024-12-18