CVE-2023-52582
What it is
In the Linux kernel, the following vulnerability has been resolved: netfs: Only call folio_start_fscache() one time for each folio If a network filesystem using netfs implements a clamp_length() function, it can set subrequest lengths smaller than a page size. When we loop through the folios in netfs_rreq_unlock_folios() to set any folios to be written back, we need to make sure we only call folio_start_fscache() once for each folio. Otherwise, this simple testcase: mount -o fsc,rsize=1024,wsize=1024 127.0.0.1:/export /mnt/nfs dd if=/dev/zero of=/mnt/nfs/file.bin bs=4096 count=1 1+0 records in 1+0 records out 4096 bytes (4.1 kB, 4.0 KiB) copied, 0.0126359 s, 324 kB/s echo 3 > /proc/sys/vm/drop_caches cat /mnt/nfs/file.bin > /dev/null will trigger an oops similar to the following: page dumped because: VM_BUG_ON_FOLIO(folio_test_private_2(folio)) ------------[ cut here ]------------ kernel BUG at include/linux/netfs.h:44! ... CPU: 5 PID: 134 Comm: kworker/u16:5 Kdump: loaded Not tainted 6.4.0-rc5 ... RIP: 0010:netfs_rreq_unlock_folios+0x68e/0x730 [netfs] ... Call Trace: netfs_rreq_assess+0x497/0x660 [netfs] netfs_subreq_terminated+0x32b/0x610 [netfs] nfs_netfs_read_completion+0x14e/0x1a0 [nfs] nfs_read_completion+0x2f9/0x330 [nfs] rpc_free_task+0x72/0xa0 [sunrpc] rpc_async_release+0x46/0x70 [sunrpc] process_one_work+0x3bd/0x710 worker_thread+0x89/0x610 kthread+0x181/0x1c0 ret_from_fork+0x29/0x50
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Record status
- Analyzed
Affected
- Linux Kernel < 6.1.56
- Linux Kernel < 6.5.6
- Linux Kernel 6.6
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2023-52582.md and follow it. Check whether this project is affected by CVE-2023-52582. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/d9f5537479d4ec97ea92ff24e81a517d5772581a
- https://git.kernel.org/stable/c/df1c357f25d808e30b216188330e708e09e1a412
- https://git.kernel.org/stable/c/df9950d37df113db59495fa09d060754366a2b7c
- https://git.kernel.org/stable/c/d9f5537479d4ec97ea92ff24e81a517d5772581a
- https://git.kernel.org/stable/c/df1c357f25d808e30b216188330e708e09e1a412
- https://git.kernel.org/stable/c/df9950d37df113db59495fa09d060754366a2b7c
References
- https://git.kernel.org/stable/c/d9f5537479d4ec97ea92ff24e81a517d5772581a
- https://git.kernel.org/stable/c/df1c357f25d808e30b216188330e708e09e1a412
- https://git.kernel.org/stable/c/df9950d37df113db59495fa09d060754366a2b7c
- https://git.kernel.org/stable/c/d9f5537479d4ec97ea92ff24e81a517d5772581a
- https://git.kernel.org/stable/c/df1c357f25d808e30b216188330e708e09e1a412
- https://git.kernel.org/stable/c/df9950d37df113db59495fa09d060754366a2b7c