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.
References
Configurations
Configuration 1 (hide)
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History
08 Nov 2024, 16:15
| Type | Values Removed | Values Added |
|---|---|---|
| References |
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25 Oct 2024, 14:43
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| First Time |
Linux linux Kernel
Linux |
|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
| CWE | CWE-476 | |
| References | () https://git.kernel.org/stable/c/11b230100d6801c014fab2afabc8bdea304c1b96 - Patch | |
| References | () https://git.kernel.org/stable/c/5b4b2dcace35f618fe361a87bae6f0d13af31bc1 - Patch | |
| References | () https://git.kernel.org/stable/c/6766937d0327000ac1b87c97bbecdd28b0dd6599 - Patch | |
| References | () https://git.kernel.org/stable/c/6801ed1298204d16a38571091e31178bfdc3c679 - Patch | |
| References | () https://git.kernel.org/stable/c/a9fcb1717d75061d3653ed69365c8d45331815cd - Patch | |
| References | () https://git.kernel.org/stable/c/b63481b3a388ee2df9e295f97273226140422a42 - Patch | |
| References | () https://git.kernel.org/stable/c/f55ecc58d07a6c1f6d6d5b5af125c25f8da0bda2 - Patch |
23 Oct 2024, 15:13
| Type | Values Removed | Values Added |
|---|---|---|
| Summary |
|
21 Oct 2024, 18:15
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2024-10-21 18:15
Updated : 2024-11-08 16:15
NVD link : CVE-2024-49881
Mitre link : CVE-2024-49881
CVE.ORG link : CVE-2024-49881
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-476
NULL Pointer Dereference