CVE-2022-50456

/// Technical description

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

btrfs: fix resolving backrefs for inline extent followed by prealloc

If a file consists of an inline extent followed by a regular or prealloc

extent, then a legitimate attempt to resolve a logical address in the

non-inline region will result in add_all_parents reading the invalid

offset field of the inline extent. If the inline extent item is placed

in the leaf eb s.t. it is the first item, attempting to access the

offset field will not only be meaningless, it will go past the end of

the eb and cause this panic:

[17.626048] BTRFS warning (device dm-2): bad eb member end: ptr 0x3fd4 start 30834688 member offset 16377 size 8

[17.631693] general protection fault, probably for non-canonical address 0x5088000000000: 0000 [#1] SMP PTI

[17.635041] CPU: 2 PID: 1267 Comm: btrfs Not tainted 5.12.0-07246-g75175d5adc74-dirty #199

[17.637969] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g15582

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References