High severity · published Sep 11, 2026
CVE-2026-89586
ata: libata-scsi: fix DSM TRIM for sector sizes larger than 2048 bytes
8.2
CVSS
0.6%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved: ata: libata-scsi: fix DSM TRIM for sector sizes larger than 2048 bytes ata_scsi_write_same_xlat() translates a SCSI WRITE SAME command with the UNMAP bit set into an ATA DATA SET MANAGEMENT TRIM command. The TRIM descriptor is built by ata_format_dsm_trim_descr() into the 2048-byte ata_scsi_rbuf staging buffer, and the number of bytes copied is compared against the logical sector size by the caller: size = ata_format_dsm_trim_descr(scmd, trmax, block, n_block); if (size != len) /* len == sdp->sector_size */ goto invalid_param_len; ata_format_dsm_trim_descr() clamps the copy length to ATA_SCSI_RBUF_SIZE (2048). On a device whose logical sector size exceeds that (e.g. a 4Kn device, where sector_size == 4096) the function can never return more than 2048, while the caller expects it to return sector_size. The comparison therefore always fails, so every TRIM is rejected with "Parameter list length error" and WARN_ON() splats on each attempt. TRIM / discard is thus completely broken on such devices. The descriptor was incorrectly sized from the logical sector size. A DSM TRIM payload is a list of 512-byte pages, each holding up to ATA_MAX_TRIM_RNUM (64) LBA Range Entries, and is independent of the logical sector size. The Block Limits VPD page already advertises a single such page as the maximum WRITE SAME length (65535 * ATA_MAX_TRIM_RNUM logical blocks), so the block layer never sends a request that needs more than one page. Emit exactly one 512-byte page, independent of the logical sector size, and transfer only that page (COUNT == 1). For a 512-byte-sector device this is unchanged; devices with larger logical sectors now work instead of failing every TRIM.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
ef2d7392c4ece5c3cd12a6c7ca9366cd8f189aff before 07975b8daa3b0ab3cbc02cc48ea7bc48fadcec53; ef2d7392c4ece5c3cd12a6c7ca9366cd8f189aff before b7b5ab2df325ffbbad7ca2debaa071e024d68cb5; ef2d7392c4ece5c3cd12a6c7ca9366cd8f189aff before 07baa310ea3224a7044b1ca84796bb37a235af1f; ef2d7392c4ece5c3cd12a6c7ca9366cd8f189aff before 977554ed91b54075fbc0bac536316b4841ef6258; ef2d7392c4ece5c3cd12a6c7ca9366cd8f189aff before 04e2befe25792f2e90097f284d7e86fc6bcfe928; ef2d7392c4ece5c3cd12a6c7ca9366cd8f189aff before c2e3dccd6870659851eaa4c12ab16418b8e3040a; +3 more · source: vendor