| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49360: f2fs: fix to do sanity check on total_data_blocks |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| f2fs: fix to do sanity check on total_data_blocks |
| |
| As Yanming reported in bugzilla: |
| |
| https://bugzilla.kernel.org/show_bug.cgi?id=215916 |
| |
| The kernel message is shown below: |
| |
| kernel BUG at fs/f2fs/segment.c:2560! |
| Call Trace: |
| allocate_segment_by_default+0x228/0x440 |
| f2fs_allocate_data_block+0x13d1/0x31f0 |
| do_write_page+0x18d/0x710 |
| f2fs_outplace_write_data+0x151/0x250 |
| f2fs_do_write_data_page+0xef9/0x1980 |
| move_data_page+0x6af/0xbc0 |
| do_garbage_collect+0x312f/0x46f0 |
| f2fs_gc+0x6b0/0x3bc0 |
| f2fs_balance_fs+0x921/0x2260 |
| f2fs_write_single_data_page+0x16be/0x2370 |
| f2fs_write_cache_pages+0x428/0xd00 |
| f2fs_write_data_pages+0x96e/0xd50 |
| do_writepages+0x168/0x550 |
| __writeback_single_inode+0x9f/0x870 |
| writeback_sb_inodes+0x47d/0xb20 |
| __writeback_inodes_wb+0xb2/0x200 |
| wb_writeback+0x4bd/0x660 |
| wb_workfn+0x5f3/0xab0 |
| process_one_work+0x79f/0x13e0 |
| worker_thread+0x89/0xf60 |
| kthread+0x26a/0x300 |
| ret_from_fork+0x22/0x30 |
| RIP: 0010:new_curseg+0xe8d/0x15f0 |
| |
| The root cause is: ckpt.valid_block_count is inconsistent with SIT table, |
| stat info indicates filesystem has free blocks, but SIT table indicates |
| filesystem has no free segment. |
| |
| So that during garbage colloection, it triggers panic when LFS allocator |
| fails to find free segment. |
| |
| This patch tries to fix this issue by checking consistency in between |
| ckpt.valid_block_count and block accounted from SIT. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49360 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 5.10.121 with commit ef221b738b26d8c9f7e7967f4586db2dd3bd5288 |
| Fixed in 5.15.46 with commit c9e4cd5b0ccd7168801d6a811919171b185c5cf8 |
| Fixed in 5.17.14 with commit 071b1269a3b3ad9cec16ed76a48015bfffd9aee8 |
| Fixed in 5.18.3 with commit cc8c9df19971e59ebbe669ce710080e347dfec32 |
| Fixed in 5.19 with commit 6b8beca0edd32075a769bfe4178ca00c0dcd22a9 |
| |
| 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-2022-49360 |
| 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/f2fs.h |
| fs/f2fs/segment.c |
| fs/f2fs/segment.h |
| |
| |
| 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/ef221b738b26d8c9f7e7967f4586db2dd3bd5288 |
| https://git.kernel.org/stable/c/c9e4cd5b0ccd7168801d6a811919171b185c5cf8 |
| https://git.kernel.org/stable/c/071b1269a3b3ad9cec16ed76a48015bfffd9aee8 |
| https://git.kernel.org/stable/c/cc8c9df19971e59ebbe669ce710080e347dfec32 |
| https://git.kernel.org/stable/c/6b8beca0edd32075a769bfe4178ca00c0dcd22a9 |
