CVE-2021-47066

published 2024-02-29

CVE-2021-47066: In the Linux kernel, the following vulnerability has been resolved: async_xor: increase src_offs when dropping destination page Now we support sharing one page…

Priority P4 19 medium 5.5 CVSS 3.1

AV L AC L PR L UI N S U C N I N A H

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

async_xor: increase src_offs when dropping destination page

Now we support sharing one page if PAGE_SIZE is not equal stripe size. To
support this, it needs to support calculating xor value with different
offsets for each r5dev. One offset array is used to record those offsets.

In RMW mode, parity page is used as a source page. It sets
ASYNC_TX_XOR_DROP_DST before calculating xor value in ops_run_prexor5.
So it needs to add src_list and src_offs at the same time. Now it only
needs src_list. So the xor value which is calculated is wrong. It can
cause data corruption problem.

I can reproduce this problem 100% on a POWER8 machine. The steps are:

mdadm -CR /dev/md0 -l5 -n3 /dev/sdb1 /dev/sdc1 /dev/sdd1 --size=3G
mkfs.xfs /dev/md0
mount /dev/md0 /mnt/test
mount: /mnt/test: mount(2) system call failed: Structure needs cleaning.

Affected

13 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 5.10.38-1 (bookworm)	linux 5.10.38-1 (bookworm)
linux	linux	—	—
linux	linux	>= 29bcff787a2593b2126cfaff612c0b4e560022e9 < cab2e8e5997b592fdb7d02cf2387b4b8e3057174	cab2e8e5997b592fdb7d02cf2387b4b8e3057174
linux	linux	>= 29bcff787a2593b2126cfaff612c0b4e560022e9 < 29ffa50f33de824b5491f8239c88c4a0efdd03af	29ffa50f33de824b5491f8239c88c4a0efdd03af
linux	linux	>= 29bcff787a2593b2126cfaff612c0b4e560022e9 < 53f8208e11abd6dde9480dfcb97fecdb1bc2ac18	53f8208e11abd6dde9480dfcb97fecdb1bc2ac18
linux	linux	>= 29bcff787a2593b2126cfaff612c0b4e560022e9 < ceaf2966ab082bbc4d26516f97b3ca8a676e2af8	ceaf2966ab082bbc4d26516f97b3ca8a676e2af8
linux	linux_kernel	>= 0 < 5.10.38-1	5.10.38-1
linux	linux_kernel	>= 0 < 5.10.38-1	5.10.38-1
linux	linux_kernel	>= 0 < 5.10.38-1	5.10.38-1
linux	linux_kernel	>= 0 < 5.10.38-1	5.10.38-1
linux	linux_kernel	>= 5.10 < 5.10.37	5.10.37
linux	linux_kernel	>= 5.11 < 5.11.21	5.11.21
linux	linux_kernel	>= 5.12 < 5.12.4	5.12.4

CVSS provenance

nvd v3.1 5.5 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

osv 5.5 MEDIUM

vendor_debian 5.5 MEDIUM

vendor_redhat 5.5 MEDIUM

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CWE-222