CVE-2021-46987

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Source

https://nvd.nist.gov/vuln/detail/CVE-2021-46987

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-46987.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2021-46987

Related

UBUNTU-CVE-2021-46987

Published

2024-02-28T09:15:37Z

Modified

2025-01-14T10:05:08.632949Z

Severity

5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator

Summary

[none]

Details

In the Linux kernel, the following vulnerability has been resolved:

btrfs: fix deadlock when cloning inline extents and using qgroups

There are a few exceptional cases where cloning an inline extent needs to copy the inline extent data into a page of the destination inode.

When this happens, we end up starting a transaction while having a dirty page for the destination inode and while having the range locked in the destination's inode iotree too. Because when reserving metadata space for a transaction we may need to flush existing delalloc in case there is not enough free space, we have a mechanism in place to prevent a deadlock, which was introduced in commit 3d45f221ce627d ("btrfs: fix deadlock when cloning inline extent and low on free metadata space").

However when using qgroups, a transaction also reserves metadata qgroup space, which can also result in flushing delalloc in case there is not enough available space at the moment. When this happens we deadlock, since flushing delalloc requires locking the file range in the inode's iotree and the range was already locked at the very beginning of the clone operation, before attempting to start the transaction.

When this issue happens, stack traces like the following are reported:

[72747.556262] task:kworker/u81:9 state:D stack: 0 pid: 225 ppid: 2 flags:0x00004000 [72747.556268] Workqueue: writeback wbworkfn (flush-btrfs-1142) [72747.556271] Call Trace: [72747.556273] _schedule+0x296/0x760 [72747.556277] schedule+0x3c/0xa0 [72747.556279] ioschedule+0x12/0x40 [72747.556284] _lockpage+0x13c/0x280 [72747.556287] ? genericfilereadonlymmap+0x70/0x70 [72747.556325] extentwritecachepages+0x22a/0x440 [btrfs] [72747.556331] ? _setpagedirtynobuffers+0xe7/0x160 [72747.556358] ? setextentbufferdirty+0x5e/0x80 [btrfs] [72747.556362] ? updategroupcapacity+0x25/0x210 [72747.556366] ? cpumasknextand+0x1a/0x20 [72747.556391] extentwritepages+0x44/0xa0 [btrfs] [72747.556394] dowritepages+0x41/0xd0 [72747.556398] _writebacksingleinode+0x39/0x2a0 [72747.556403] writebacksbinodes+0x1ea/0x440 [72747.556407] _writebackinodeswb+0x5f/0xc0 [72747.556410] wbwriteback+0x235/0x2b0 [72747.556414] ? getnrinodes+0x35/0x50 [72747.556417] wbworkfn+0x354/0x490 [72747.556420] ? newidlebalance+0x2c5/0x3e0 [72747.556424] processonework+0x1aa/0x340 [72747.556426] workerthread+0x30/0x390 [72747.556429] ? createworker+0x1a0/0x1a0 [72747.556432] kthread+0x116/0x130 [72747.556435] ? kthreadpark+0x80/0x80 [72747.556438] retfromfork+0x1f/0x30

[72747.566958] Workqueue: btrfs-flushdelalloc btrfsworkhelper [btrfs] [72747.566961] Call Trace: [72747.566964] _schedule+0x296/0x760 [72747.566968] ? finishwait+0x80/0x80 [72747.566970] schedule+0x3c/0xa0 [72747.566995] waitextentbit.constprop.68+0x13b/0x1c0 [btrfs] [72747.566999] ? finishwait+0x80/0x80 [72747.567024] lockextentbits+0x37/0x90 [btrfs] [72747.567047] btrfsinvalidatepage+0x299/0x2c0 [btrfs] [72747.567051] ? findgetpagesrangetag+0x2cd/0x380 [72747.567076] _extentwritepage+0x203/0x320 [btrfs] [72747.567102] extentwritecachepages+0x2bb/0x440 [btrfs] [72747.567106] ? updateloadavg+0x7e/0x5f0 [72747.567109] ? enqueueentity+0xf4/0x6f0 [72747.567134] extentwritepages+0x44/0xa0 [btrfs] [72747.567137] ? enqueuetaskfair+0x93/0x6f0 [72747.567140] dowritepages+0x41/0xd0 [72747.567144] _filemapfdatawriterange+0xc7/0x100 [72747.567167] btrfsrundelallocwork+0x17/0x40 [btrfs] [72747.567195] btrfsworkhelper+0xc2/0x300 [btrfs] [72747.567200] processonework+0x1aa/0x340 [72747.567202] workerthread+0x30/0x390 [72747.567205] ? createworker+0x1a0/0x1a0 [72747.567208] kthread+0x116/0x130 [72747.567211] ? kthreadpark+0x80/0x80 [72747.567214] retfromfork+0x1f/0x30

[72747.569686] task:fsstress state:D stack:
---truncated---

References

Affected packages

Debian:11 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

5.*

5.10.46-4

5.10.46-5

5.10.70-1~bpo10+1

5.10.70-1

5.10.84-1

5.10.92-1~bpo10+1

5.10.92-1

5.10.92-2

5.10.103-1~bpo10+1

5.10.103-1

5.10.106-1

5.10.113-1

5.10.120-1~bpo10+1

5.10.120-1

5.10.127-1

5.10.127-2~bpo10+1

5.10.127-2

5.10.136-1

5.10.140-1

5.10.148-1

5.10.149-1

5.10.149-2

5.10.158-1

5.10.158-2

5.10.162-1

5.10.178-1

5.10.178-2

5.10.178-3

5.10.179-1

5.10.179-2

5.10.179-3

5.10.179-4

5.10.179-5

5.10.191-1

5.10.197-1

5.10.205-1

5.10.205-2

5.10.209-1

5.10.209-2

5.10.216-1

5.10.218-1

5.10.221-1

5.10.223-1

5.10.226-1

5.13.9-1~exp1

5.13.9-1~exp2

5.13.12-1~exp1

5.14-1~exp1

5.14-1~exp2

5.14.1-1~exp1

5.14.2-1~exp1

5.14.3-1~exp1

5.14.6-1

5.14.6-2

5.14.6-3

5.14.9-1

5.14.9-2~bpo11+1

5.14.9-2

5.14.12-1

5.14.16-1

5.15-1~exp1

5.15.1-1~exp1

5.15.2-1~exp1

5.15.3-1

5.15.5-1

5.15.5-2~bpo11+1

5.15.5-2

5.15.15-1

5.15.15-2~bpo11+1

5.15.15-2

5.16~rc1-1~exp1

5.16~rc3-1~exp1

5.16~rc4-1~exp1

5.16~rc5-1~exp1

5.16~rc6-1~exp1

5.16~rc7-1~exp1

5.16~rc8-1~exp1

5.16.3-1~exp1

5.16.4-1~exp1

5.16.7-1

5.16.7-2

5.16.10-1

5.16.11-1~bpo11+1

5.16.11-1

5.16.12-1~bpo11+1

5.16.12-1

5.16.14-1

5.16.18-1

5.17~rc3-1~exp1

5.17~rc4-1~exp1

5.17~rc5-1~exp1

5.17~rc6-1~exp1

5.17~rc7-1~exp1

5.17~rc8-1~exp1

5.17.1-1~exp1

5.17.3-1

5.17.6-1

5.17.11-1

5.18-1~exp1

5.18.2-1~bpo11+1

5.18.2-1

5.18.5-1

5.18.14-1~bpo11+1

5.18.14-1

5.18.16-1~bpo11+1

5.18.16-1

5.19~rc4-1~exp1

5.19~rc6-1~exp1

5.19-1~exp1

5.19.6-1

5.19.11-1~bpo11+1

5.19.11-1

6.*

6.0~rc7-1~exp1

6.0-1~exp1

6.0.2-1

6.0.3-1~bpo11+1

6.0.3-1

6.0.5-1

6.0.6-1

6.0.6-2

6.0.7-1

6.0.8-1

6.0.10-1

6.0.10-2

6.0.12-1~bpo11+1

6.0.12-1

6.0.12-1+alpha

6.1~rc3-1~exp1

6.1~rc5-1~exp1

6.1~rc6-1~exp1

6.1~rc7-1~exp1

6.1~rc8-1~exp1

6.1.1-1~exp1

6.1.1-1~exp2

6.1.2-1~exp1

6.1.4-1

6.1.7-1

6.1.8-1

6.1.8-1+sh4

6.1.11-1

6.1.12-1~bpo11+1

6.1.12-1

6.1.15-1~bpo11+1

6.1.15-1

6.1.20-1~bpo11+1

6.1.20-1

6.1.20-2~bpo11+1

6.1.20-2

6.1.25-1

6.1.27-1~bpo11+1

6.1.27-1

6.1.37-1

6.1.38-1

6.1.38-2~bpo11+1

6.1.38-2

6.1.38-3

6.1.38-4~bpo11+1

6.1.38-4

6.1.52-1

6.1.55-1~bpo11+1

6.1.55-1

6.1.64-1

6.1.66-1

6.1.67-1

6.1.69-1~bpo11+1

6.1.69-1

6.1.76-1~bpo11+1

6.1.76-1

6.1.82-1

6.1.85-1

6.1.90-1~bpo11+1

6.1.90-1

6.1.94-1~bpo11+1

6.1.94-1

6.1.98-1

6.1.99-1

6.1.106-1

6.1.106-2

6.1.106-3

6.1.112-1

6.1.115-1

6.1.119-1

6.1.123-1

6.1.124-1

6.3.1-1~exp1

6.3.2-1~exp1

6.3.4-1~exp1

6.3.5-1~exp1

6.3.7-1~bpo12+1

6.3.7-1

6.3.11-1

6.4~rc6-1~exp1

6.4~rc7-1~exp1

6.4.1-1~exp1

6.4.4-1~bpo12+1

6.4.4-1

6.4.4-2

6.4.4-3~bpo12+1

6.4.4-3

6.4.11-1

6.4.13-1

6.5~rc4-1~exp1

6.5~rc6-1~exp1

6.5~rc7-1~exp1

6.5.1-1~exp1

6.5.3-1~bpo12+1

6.5.3-1

6.5.6-1

6.5.8-1

6.5.10-1~bpo12+1

6.5.10-1

6.5.13-1

6.6.3-1~exp1

6.6.4-1~exp1

6.6.7-1~exp1

6.6.8-1

6.6.9-1

6.6.11-1

6.6.13-1~bpo12+1

6.6.13-1

6.6.15-1

6.6.15-2

6.7-1~exp1

6.7.1-1~exp1

6.7.4-1~exp1

6.7.7-1

6.7.9-1

6.7.9-2

6.7.12-1~bpo12+1

6.7.12-1

6.8.9-1

6.8.11-1

6.8.12-1~bpo12+1

6.8.12-1

6.9.2-1~exp1

6.9.7-1~bpo12+1

6.9.7-1

6.9.8-1

6.9.9-1

6.9.10-1~bpo12+1

6.9.10-1

6.9.11-1

6.9.12-1

6.10-1~exp1

6.10.1-1~exp1

6.10.3-1

6.10.4-1

6.10.6-1~bpo12+1

6.10.6-1

6.10.7-1

6.10.9-1

6.10.11-1~bpo12+1

6.10.11-1

6.10.12-1

6.11~rc4-1~exp1

6.11~rc5-1~exp1

6.11-1~exp1

6.11.2-1

6.11.4-1

6.11.5-1~bpo12+1

6.11.5-1

6.11.6-1

6.11.7-1

6.11.9-1

6.11.10-1~bpo12+1

6.11.10-1

6.12~rc6-1~exp1

6.12.3-1

6.12.5-1

6.12.6-1

6.12.8-1

6.12.9-1

6.13~rc6-1~exp1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:12 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

5.14.6-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:13 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

5.14.6-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}