CVE-2022-50428: In the Linux kernel, the following vulnerability has been resolved: ext4: fix off-by-one errors in fast-commit block filling Due to several different…

PriorityP420medium5.5CVSS 3.1

AVLACLPRLUINSUCNINAH

EPSS

0.15%

4.4th percentile

In the Linux kernel, the following vulnerability has been resolved: ext4: fix off-by-one errors in fast-commit block filling Due to several different off-by-one errors, or perhaps due to a late change in design that wasn't fully reflected in the code that was actually merged, there are several very strange constraints on how fast-commit blocks are filled with tlv entries: - tlvs must start at least 10 bytes before the end of the block, even though the minimum tlv length is 8. Otherwise, the replay code will ignore them. (BUG: ext4_fc_reserve_space() could violate this requirement if called with a len of blocksize - 9 or blocksize - 8. Fortunately, this doesn't seem to happen currently.) - tlvs must end at least 1 byte before the end of the block. Otherwise the replay code will consider them to be invalid. This quirk contributed to a bug (fixed by an earlier commit) where uninitialized memory was being leaked to disk in the last byte of blocks. Also, strangely these constraints don't apply to the replay code in e2fsprogs, which will accept any tlvs in the blocks (with no bounds checks at all, but that is a separate issue...). Given that this all seems to be a bug, let's fix it by just filling blocks with tlv entries in the natural way. Note that old kernels will be unable to replay fast-commit journals created by kernels that have this commit.

Affected

12 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 6.1.4-1 (bookworm)	linux 6.1.4-1 (bookworm)
linux	linux	—	—
linux	linux	>= aa75f4d3daaeb1389b9cce9d6b84401eaf228d4e < 18f28f13301d1afb8cea9c4ddcecdbff14488ec6	18f28f13301d1afb8cea9c4ddcecdbff14488ec6
linux	linux	>= aa75f4d3daaeb1389b9cce9d6b84401eaf228d4e < 5ca65dffdead16572ca046c43fb576b227f7f635	5ca65dffdead16572ca046c43fb576b227f7f635
linux	linux	>= aa75f4d3daaeb1389b9cce9d6b84401eaf228d4e < 5439ad45c0d0c8db41eb6f4dce6f778f15a5ee16	5439ad45c0d0c8db41eb6f4dce6f778f15a5ee16
linux	linux	>= aa75f4d3daaeb1389b9cce9d6b84401eaf228d4e < 48a6a66db82b8043d298a630f22c62d43550cae5	48a6a66db82b8043d298a630f22c62d43550cae5
linux	linux_kernel	>= 0 < 6.1.4-1	6.1.4-1
linux	linux_kernel	>= 0 < 6.1.4-1	6.1.4-1
linux	linux_kernel	>= 0 < 6.1.4-1	6.1.4-1
linux	linux_kernel	>= 5.10 < 5.15.87	5.15.87
linux	linux_kernel	>= 5.16 < 6.0.18	6.0.18
linux	linux_kernel	>= 6.1 < 6.1.4	6.1.4

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

osv5.5MEDIUM

vendor_debian5.5MEDIUM

vendor_redhat5.5MEDIUM

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