SecuriTricks - CVE-2024-46701

Description

In the Linux kernel, the following vulnerability has been resolved: libfs: fix infinite directory reads for offset dir After we switch tmpfs dir operations from simple_dir_operations to simple_offset_dir_operations, every rename happened will fill new dentry to dest dir's maple tree(&SHMEM_I(inode)->dir_offsets->mt) with a free key starting with octx->newx_offset, and then set newx_offset equals to free key + 1. This will lead to infinite readdir combine with rename happened at the same time, which fail generic/736 in xfstests(detail show as below). 1. create 5000 files(1 2 3...) under one dir 2. call readdir(man 3 readdir) once, and get one entry 3. rename(entry, "TEMPFILE"), then rename("TEMPFILE", entry) 4. loop 2~3, until readdir return nothing or we loop too many times(tmpfs break test with the second condition) We choose the same logic what commit 9b378f6ad48cf ("btrfs: fix infinite directory reads") to fix it, record the last_index when we open dir, and do not emit the entry which index >= last_index. The file->private_data now used in offset dir can use directly to do this, and we also update the last_index when we llseek the dir file. [brauner: only update last_index after seek when offset is zero like Jan suggested]

Product(s) Impacted

Vendor	Product	Versions
Linux	Linux Kernel	*, 6.11

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.

*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	6.11	rc1	/	/	/	/	/	/
o	linux	linux_kernel	6.11	rc2	/	/	/	/	/	/
o	linux	linux_kernel	6.11	rc3	/	/	/	/	/	/

References

https://git.kernel.org/stable/c/308b4fc2403b335894592ee9dc212a5e58bb309f

https://git.kernel.org/stable/c/64a7ce76fb901bf9f9c36cf5d681328fc0fd4b5a

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: Sept. 13, 2024, 7:15 a.m.
Last Modified: Sept. 19, 2024, 1:40 p.m.

Status : Analyzed

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

More info

Source

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

CVE-2024-46701