| 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-2022-49347: ext4: fix bug_on in ext4_writepages |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ext4: fix bug_on in ext4_writepages |
| |
| we got issue as follows: |
| EXT4-fs error (device loop0): ext4_mb_generate_buddy:1141: group 0, block bitmap and bg descriptor inconsistent: 25 vs 31513 free cls |
| ------------[ cut here ]------------ |
| kernel BUG at fs/ext4/inode.c:2708! |
| invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI |
| CPU: 2 PID: 2147 Comm: rep Not tainted 5.18.0-rc2-next-20220413+ #155 |
| RIP: 0010:ext4_writepages+0x1977/0x1c10 |
| RSP: 0018:ffff88811d3e7880 EFLAGS: 00010246 |
| RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88811c098000 |
| RDX: 0000000000000000 RSI: ffff88811c098000 RDI: 0000000000000002 |
| RBP: ffff888128140f50 R08: ffffffffb1ff6387 R09: 0000000000000000 |
| R10: 0000000000000007 R11: ffffed10250281ea R12: 0000000000000001 |
| R13: 00000000000000a4 R14: ffff88811d3e7bb8 R15: ffff888128141028 |
| FS: 00007f443aed9740(0000) GS:ffff8883aef00000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 0000000020007200 CR3: 000000011c2a4000 CR4: 00000000000006e0 |
| DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 |
| DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 |
| Call Trace: |
| <TASK> |
| do_writepages+0x130/0x3a0 |
| filemap_fdatawrite_wbc+0x83/0xa0 |
| filemap_flush+0xab/0xe0 |
| ext4_alloc_da_blocks+0x51/0x120 |
| __ext4_ioctl+0x1534/0x3210 |
| __x64_sys_ioctl+0x12c/0x170 |
| do_syscall_64+0x3b/0x90 |
| |
| It may happen as follows: |
| 1. write inline_data inode |
| vfs_write |
| new_sync_write |
| ext4_file_write_iter |
| ext4_buffered_write_iter |
| generic_perform_write |
| ext4_da_write_begin |
| ext4_da_write_inline_data_begin -> If inline data size too |
| small will allocate block to write, then mapping will has |
| dirty page |
| ext4_da_convert_inline_data_to_extent ->clear EXT4_STATE_MAY_INLINE_DATA |
| 2. fallocate |
| do_vfs_ioctl |
| ioctl_preallocate |
| vfs_fallocate |
| ext4_fallocate |
| ext4_convert_inline_data |
| ext4_convert_inline_data_nolock |
| ext4_map_blocks -> fail will goto restore data |
| ext4_restore_inline_data |
| ext4_create_inline_data |
| ext4_write_inline_data |
| ext4_set_inode_state -> set inode EXT4_STATE_MAY_INLINE_DATA |
| 3. writepages |
| __ext4_ioctl |
| ext4_alloc_da_blocks |
| filemap_flush |
| filemap_fdatawrite_wbc |
| do_writepages |
| ext4_writepages |
| if (ext4_has_inline_data(inode)) |
| BUG_ON(ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) |
| |
| The root cause of this issue is we destory inline data until call |
| ext4_writepages under delay allocation mode. But there maybe already |
| convert from inline to extent. To solve this issue, we call |
| filemap_flush first.. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49347 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 4.9.318 with commit 19918ec7717d87d5ab825884a46b26b21375d7ce |
| Fixed in 4.14.283 with commit b2b78f5bf2d453dda3903955efee059260787a42 |
| Fixed in 4.19.247 with commit de1732b5c1693ad489c5d254f124f67cb775f37d |
| Fixed in 5.4.198 with commit 73fd5b19285197078ee8a2e651d75d5b094a4de9 |
| Fixed in 5.10.121 with commit 1b061af037646c9cdb0afd8a8d2f1e1c06285866 |
| Fixed in 5.15.46 with commit 18a759f7f99f0b65a08ff5b7e745fc405a42bde4 |
| Fixed in 5.17.14 with commit 1cde35417edc0370fb0179a4e38b78a15350a8d0 |
| Fixed in 5.18.3 with commit 013f12bdedb96816aaa27ee04349f4433d361f52 |
| Fixed in 5.19 with commit ef09ed5d37b84d18562b30cf7253e57062d0db05 |
| |
| 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-2022-49347 |
| 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/ext4/inline.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/19918ec7717d87d5ab825884a46b26b21375d7ce |
| https://git.kernel.org/stable/c/b2b78f5bf2d453dda3903955efee059260787a42 |
| https://git.kernel.org/stable/c/de1732b5c1693ad489c5d254f124f67cb775f37d |
| https://git.kernel.org/stable/c/73fd5b19285197078ee8a2e651d75d5b094a4de9 |
| https://git.kernel.org/stable/c/1b061af037646c9cdb0afd8a8d2f1e1c06285866 |
| https://git.kernel.org/stable/c/18a759f7f99f0b65a08ff5b7e745fc405a42bde4 |
| https://git.kernel.org/stable/c/1cde35417edc0370fb0179a4e38b78a15350a8d0 |
| https://git.kernel.org/stable/c/013f12bdedb96816aaa27ee04349f4433d361f52 |
| https://git.kernel.org/stable/c/ef09ed5d37b84d18562b30cf7253e57062d0db05 |
