Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.1.12 and classified as problematic. This vulnerability affects the function nilfs_resize_fs of the component nilfs2. The manipulation leads to out-of-bounds. This vulnerability was named CVE-2023-52705. There is no exploit available. It is recommended to upgrade the affected component. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 6.1.12. This affects the function nilfs_resize_fs of the component nilfs2. The manipulation with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix underflow in second superblock position calculations Macro NILFS_SB2_OFFSET_BYTES, which computes the position of the second superblock, underflows when the argument device size is less than 4096 bytes. Therefore, when using this macro, it is necessary to check in advance that the device size is not less than a lower limit, or at least that underflow does not occur. The current nilfs2 implementation lacks this check, causing out-of-bound block access when mounting devices smaller than 4096 bytes: I/O error, dev loop0, sector 36028797018963960 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 NILFS (loop0): unable to read secondary superblock (blocksize = 1024) In addition, when trying to resize the filesystem to a size below 4096 bytes, this underflow occurs in nilfs_resize_fs(), passing a huge number of segments to nilfs_sufile_resize(), corrupting parameters such as the number of segments in superblocks. This causes excessive loop iterations in nilfs_sufile_resize() during a subsequent resize ioctl, causing semaphore ns_segctor_sem to block for a long time and hang the writer thread: INFO: task segctord:5067 blocked for more than 143 seconds. Not tainted 6.2.0-rc8-syzkaller-00015-gf6feea56f66d #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:segctord state:D stack:23456 pid:5067 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5293 [inline] __schedule+0x1409/0x43f0 kernel/sched/core.c:6606 schedule+0xc3/0x190 kernel/sched/core.c:6682 rwsem_down_write_slowpath+0xfcf/0x14a0 kernel/locking/rwsem.c:1190 nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2486 [inline] nilfs_segctor_thread+0x52f/0x1140 fs/nilfs2/segment.c:2570 kthread+0x270/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 ... Call Trace: folio_mark_accessed+0x51c/0xf00 mm/swap.c:515 __nilfs_get_page_block fs/nilfs2/page.c:42 [inline] nilfs_grab_buffer+0x3d3/0x540 fs/nilfs2/page.c:61 nilfs_mdt_submit_block+0xd7/0x8f0 fs/nilfs2/mdt.c:121 nilfs_mdt_read_block+0xeb/0x430 fs/nilfs2/mdt.c:176 nilfs_mdt_get_block+0x12d/0xbb0 fs/nilfs2/mdt.c:251 nilfs_sufile_get_segment_usage_block fs/nilfs2/sufile.c:92 [inline] nilfs_sufile_truncate_range fs/nilfs2/sufile.c:679 [inline] nilfs_sufile_resize+0x7a3/0x12b0 fs/nilfs2/sufile.c:777 nilfs_resize_fs+0x20c/0xed0 fs/nilfs2/super.c:422 nilfs_ioctl_resize fs/nilfs2/ioctl.c:1033 [inline] nilfs_ioctl+0x137c/0x2440 fs/nilfs2/ioctl.c:1301 ... This fixes these issues by inserting appropriate minimum device size checks or anti-underflow checks, depending on where the macro is used.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2023-52705 since 03/07/2024. The exploitability is told to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 239742 (TencentOS Server 2: kernel (TSSA-2024:1030)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.306, 4.19.273, 5.4.232, 5.10.169, 5.15.95 or 6.1.13 eliminates this vulnerability. Applying the patch 2f7a1135b202/b96591e2c35c/52844d8382cd/0ee5ed0126a2/a158782b56b0/a8ef5109f93c/99b9402a36f0 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (239742). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.14.305
• 4.19.272
• 5.4.231
• 5.10.168
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.15.49
• 5.15.50
• 5.15.51
• 5.15.52
• 5.15.53
• 5.15.54
• 5.15.55
• 5.15.56
• 5.15.57
• 5.15.58
• 5.15.59
• 5.15.60
• 5.15.61
• 5.15.62
• 5.15.63
• 5.15.64
• 5.15.65
• 5.15.66
• 5.15.67
• 5.15.68
• 5.15.69
• 5.15.70
• 5.15.71
• 5.15.72
• 5.15.73
• 5.15.74
• 5.15.75
• 5.15.76
• 5.15.77
• 5.15.78
• 5.15.79
• 5.15.80
• 5.15.81
• 5.15.82
• 5.15.83
• 5.15.84
• 5.15.85
• 5.15.86
• 5.15.87
• 5.15.88
• 5.15.89
• 5.15.90
• 5.15.91
• 5.15.92
• 5.15.93
• 5.15.94
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12

License

• open-source

CPE 2.3info

• 🔍
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CPE 2.2info

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