| 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-2021-47145: btrfs: do not BUG_ON in link_to_fixup_dir |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| btrfs: do not BUG_ON in link_to_fixup_dir |
| |
| While doing error injection testing I got the following panic |
| |
| kernel BUG at fs/btrfs/tree-log.c:1862! |
| invalid opcode: 0000 [#1] SMP NOPTI |
| CPU: 1 PID: 7836 Comm: mount Not tainted 5.13.0-rc1+ #305 |
| Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 |
| RIP: 0010:link_to_fixup_dir+0xd5/0xe0 |
| RSP: 0018:ffffb5800180fa30 EFLAGS: 00010216 |
| RAX: fffffffffffffffb RBX: 00000000fffffffb RCX: ffff8f595287faf0 |
| RDX: ffffb5800180fa37 RSI: ffff8f5954978800 RDI: 0000000000000000 |
| RBP: ffff8f5953af9450 R08: 0000000000000019 R09: 0000000000000001 |
| R10: 000151f408682970 R11: 0000000120021001 R12: ffff8f5954978800 |
| R13: ffff8f595287faf0 R14: ffff8f5953c77dd0 R15: 0000000000000065 |
| FS: 00007fc5284c8c40(0000) GS:ffff8f59bbd00000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 00007fc5287f47c0 CR3: 000000011275e002 CR4: 0000000000370ee0 |
| Call Trace: |
| replay_one_buffer+0x409/0x470 |
| ? btree_read_extent_buffer_pages+0xd0/0x110 |
| walk_up_log_tree+0x157/0x1e0 |
| walk_log_tree+0xa6/0x1d0 |
| btrfs_recover_log_trees+0x1da/0x360 |
| ? replay_one_extent+0x7b0/0x7b0 |
| open_ctree+0x1486/0x1720 |
| btrfs_mount_root.cold+0x12/0xea |
| ? __kmalloc_track_caller+0x12f/0x240 |
| legacy_get_tree+0x24/0x40 |
| vfs_get_tree+0x22/0xb0 |
| vfs_kern_mount.part.0+0x71/0xb0 |
| btrfs_mount+0x10d/0x380 |
| ? vfs_parse_fs_string+0x4d/0x90 |
| legacy_get_tree+0x24/0x40 |
| vfs_get_tree+0x22/0xb0 |
| path_mount+0x433/0xa10 |
| __x64_sys_mount+0xe3/0x120 |
| do_syscall_64+0x3d/0x80 |
| entry_SYSCALL_64_after_hwframe+0x44/0xae |
| |
| We can get -EIO or any number of legitimate errors from |
| btrfs_search_slot(), panicing here is not the appropriate response. The |
| error path for this code handles errors properly, simply return the |
| error. |
| |
| The Linux kernel CVE team has assigned CVE-2021-47145 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 4.4.271 with commit 76bfd8ac20bebeae599452a03dfc5724c0475dcf |
| Fixed in 4.9.271 with commit e934c4ee17b33bafb0444f2f9766cda7166d3c40 |
| Fixed in 4.14.235 with commit 0eaf383c6a4a83c09f60fd07a1bea9f1a9181611 |
| Fixed in 4.19.193 with commit 6eccfb28f8dca70c9b1b3bb3194ca54cbe73a9fa |
| Fixed in 5.4.124 with commit 0ed102453aa1cd12fefde8f6b60b9519b0b1f003 |
| Fixed in 5.10.42 with commit 7e13db503918820e6333811cdc6f151dcea5090a |
| Fixed in 5.12.9 with commit b545442133580dcb2f2496133bf850824d41255c |
| Fixed in 5.13 with commit 91df99a6eb50d5a1bc70fff4a09a0b7ae6aab96d |
| |
| 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-2021-47145 |
| 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/btrfs/tree-log.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/76bfd8ac20bebeae599452a03dfc5724c0475dcf |
| https://git.kernel.org/stable/c/e934c4ee17b33bafb0444f2f9766cda7166d3c40 |
| https://git.kernel.org/stable/c/0eaf383c6a4a83c09f60fd07a1bea9f1a9181611 |
| https://git.kernel.org/stable/c/6eccfb28f8dca70c9b1b3bb3194ca54cbe73a9fa |
| https://git.kernel.org/stable/c/0ed102453aa1cd12fefde8f6b60b9519b0b1f003 |
| https://git.kernel.org/stable/c/7e13db503918820e6333811cdc6f151dcea5090a |
| https://git.kernel.org/stable/c/b545442133580dcb2f2496133bf850824d41255c |
| https://git.kernel.org/stable/c/91df99a6eb50d5a1bc70fff4a09a0b7ae6aab96d |
