| From bippy-1.2.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2025-23130: f2fs: fix to avoid panic once fallocation fails for pinfile |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| f2fs: fix to avoid panic once fallocation fails for pinfile |
| |
| syzbot reports a f2fs bug as below: |
| |
| ------------[ cut here ]------------ |
| kernel BUG at fs/f2fs/segment.c:2746! |
| CPU: 0 UID: 0 PID: 5323 Comm: syz.0.0 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 |
| RIP: 0010:get_new_segment fs/f2fs/segment.c:2746 [inline] |
| RIP: 0010:new_curseg+0x1f52/0x1f70 fs/f2fs/segment.c:2876 |
| Call Trace: |
| <TASK> |
| __allocate_new_segment+0x1ce/0x940 fs/f2fs/segment.c:3210 |
| f2fs_allocate_new_section fs/f2fs/segment.c:3224 [inline] |
| f2fs_allocate_pinning_section+0xfa/0x4e0 fs/f2fs/segment.c:3238 |
| f2fs_expand_inode_data+0x696/0xca0 fs/f2fs/file.c:1830 |
| f2fs_fallocate+0x537/0xa10 fs/f2fs/file.c:1940 |
| vfs_fallocate+0x569/0x6e0 fs/open.c:327 |
| do_vfs_ioctl+0x258c/0x2e40 fs/ioctl.c:885 |
| __do_sys_ioctl fs/ioctl.c:904 [inline] |
| __se_sys_ioctl+0x80/0x170 fs/ioctl.c:892 |
| do_syscall_x64 arch/x86/entry/common.c:52 [inline] |
| do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 |
| entry_SYSCALL_64_after_hwframe+0x77/0x7f |
| |
| Concurrent pinfile allocation may run out of free section, result in |
| panic in get_new_segment(), let's expand pin_sem lock coverage to |
| include f2fs_gc(), so that we can make sure to reclaim enough free |
| space for following allocation. |
| |
| In addition, do below changes to enhance error path handling: |
| - call f2fs_bug_on() only in non-pinfile allocation path in |
| get_new_segment(). |
| - call reset_curseg_fields() to reset all fields of curseg in |
| new_curseg() |
| |
| The Linux kernel CVE team has assigned CVE-2025-23130 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.5 with commit f5a53edcf01eae21dc3ef1845515229e8459e5cc and fixed in 6.14.2 with commit 9392862608d081a8346a3b841f862d732fce954b |
| Issue introduced in 5.5 with commit f5a53edcf01eae21dc3ef1845515229e8459e5cc and fixed in 6.15 with commit 48ea8b200414ac69ea96f4c231f5c7ef1fbeffef |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2025-23130 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| fs/f2fs/file.c |
| fs/f2fs/segment.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/9392862608d081a8346a3b841f862d732fce954b |
| https://git.kernel.org/stable/c/48ea8b200414ac69ea96f4c231f5c7ef1fbeffef |
