# CVE-2024-47741: linux: In the Linux kernel, the following vulnerability has been resolved:  btrfs: fix race setting file private on concurre...

CVE-2024-47741 is fixed in 26 products on 1 platform, first by DEBIAN-CVE-2024-47741, released October 21, 2024. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2024-47741
- Priority: High
- CVSS: 7.0 (high)
- EPSS: 0.0017
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 21, 2024

## Description

In the Linux kernel, the following vulnerability has been resolved:  btrfs: fix race setting file private on concurrent lseek using same fd  When doing concurrent lseek(2) system calls against the same file descriptor, using multiple threads belonging to the same process, we have a short time window where a race happens and can result in a memory leak.  The race happens like this:  1) A program opens a file descriptor for a file and then spawns two    threads (with the pthreads library for example), lets call them    task A and task B;  2) Task A calls lseek with SEEK_DATA or SEEK_HOLE and ends up at    file.c:find_desired_extent() while holding a read lock on the inode;  3) At the start of find_desired_extent(), it extracts the file's    private_data pointer into a local variable named 'private', which has    a value of NULL;  4) Task B also calls lseek with SEEK_DATA or SEEK_HOLE, locks the inode    in shared mode and enters file.c:find_desired_extent(), where it also    extracts file->private_data into its local variable 'private', which    has a NULL value;  5) Because it saw a NULL file private, task A allocates a private    structure and assigns to the file structure;  6) Task B also saw a NULL file private so it also allocates its own file    private and then assigns it to the same file structure, since both    tasks are using the same file descriptor.     At this point we leak the private structure allocated by task A.  Besides the memory leak, there's also the detail that both tasks end up using the same cached state record in the private structure (struct btrfs_file_private::llseek_cached_state), which can result in a use-after-free problem since one task can free it while the other is still using it (only one task took a reference count on it). Also, sharing the cached state is not a good idea since it could result in incorrect results in the future - right now it should not be a problem because it end ups being used only in extent-io-tree.c:count_range_bits() where we do range validation before using the cached state.  Fix this by protecting the private assignment and check of a file while holding the inode's spinlock and keep track of the task that allocated the private, so that it's used only by that task in order to prevent user-after-free issues with the cached state record as well as potentially using it incorrectly in the future.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | dtb-aarch64 opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-64kb opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-64kb sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-azure opensuse-leap 15.6 | 6.4.0-150600.8.17.2 | [SUSE-SU-2024:3984-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3984-1.md) | Nov 13, 2024 |
| Linux | kernel-azure sles 15.6 | 6.4.0-150600.8.17.2 | [SUSE-SU-2024:3984-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3984-1.md) | Nov 13, 2024 |
| Linux | kernel-coco sles 15.6 | 6.4.0-15061.9.coco15sp6.1 | [SUSE-SU-2024:4387-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4387-1.md) | Dec 19, 2024 |
| Linux | kernel-coco_debug sles 15.6 | 6.4.0-15061.9.coco15sp6.1 | [SUSE-SU-2024:4387-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4387-1.md) | Dec 19, 2024 |
| Linux | kernel-debug opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-default opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-default sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-default-base opensuse-leap 15.6 | 6.4.0-150600.23.30.1.150600.12.12.6 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-default-base sles 15.6 | 6.4.0-150600.23.30.1.150600.12.12.6 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-docs opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-docs sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-kvmsmall opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-livepatch-SLE15-SP6-RT_Update_5 sles 15.6 | 1-150600.1.3.1 | [SUSE-SU-2024:3986-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3986-1.md) | Nov 13, 2024 |
| Linux | kernel-livepatch-SLE15-SP6_Update_6 sles 15.6 | 1-150600.13.3.5 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-obs-build opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-obs-build sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-obs-qa opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-rt opensuse-leap 15.6 | 6.4.0-150600.10.17.1 | [SUSE-SU-2024:3986-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3986-1.md) | Nov 13, 2024 |
| Linux | kernel-rt_debug opensuse-leap 15.6 | 6.4.0-150600.10.17.1 | [SUSE-SU-2024:3986-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3986-1.md) | Nov 13, 2024 |
| Linux | kernel-source opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-source sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-source-azure opensuse-leap 15.6 | 6.4.0-150600.8.17.1 | [SUSE-SU-2024:3984-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3984-1.md) | Nov 13, 2024 |
| Linux | kernel-source-azure sles 15.6 | 6.4.0-150600.8.17.1 | [SUSE-SU-2024:3984-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3984-1.md) | Nov 13, 2024 |
| Linux | kernel-source-coco sles 15.6 | 6.4.0-15061.9.coco15sp6.1 | [SUSE-SU-2024:4387-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4387-1.md) | Dec 19, 2024 |
| Linux | kernel-source-rt opensuse-leap 15.6 | 6.4.0-150600.10.17.1 | [SUSE-SU-2024:3986-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3986-1.md) | Nov 13, 2024 |
| Linux | kernel-syms opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-syms sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-syms-azure opensuse-leap 15.6 | 6.4.0-150600.8.17.1 | [SUSE-SU-2024:3984-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3984-1.md) | Nov 13, 2024 |
| Linux | kernel-syms-azure sles 15.6 | 6.4.0-150600.8.17.1 | [SUSE-SU-2024:3984-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3984-1.md) | Nov 13, 2024 |
| Linux | kernel-syms-coco sles 15.6 | 6.4.0-15061.9.coco15sp6.1 | [SUSE-SU-2024:4387-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4387-1.md) | Dec 19, 2024 |
| Linux | kernel-syms-rt opensuse-leap 15.6 | 6.4.0-150600.10.17.1 | [SUSE-SU-2024:3986-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-3986-1.md) | Nov 13, 2024 |
| Linux | kernel-zfcpdump opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | kernel-zfcpdump sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 |
| Linux | linux Debian 13.5 (trixie) | 6.11.2-1 | [DEBIAN-CVE-2024-47741](https://patchblox.com/security/data/fix/linux/debian-cve-2024-47741.md) | Oct 21, 2024 |
| Linux | linux Debian 14 | 6.11.2-1 | [DEBIAN-CVE-2024-47741](https://patchblox.com/security/data/fix/linux/debian-cve-2024-47741.md) | Oct 21, 2024 |

---

Data as of 2026-11-07T18:46:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.
