HIGH
scsi AioCmd Uninitialized
CVE-2026-43055
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
KernelScan AI7.5HIGH
01Description
In the Linux kernel, the following vulnerability has been resolved: scsi: target: file: Use kzalloc_flex for aio_cmd The target_core_file doesn't initialize the aio_cmd->iocb for the ki_write_stream. When a write command fd_execute_rw_aio() is executed, we may get a bogus ki_write_stream value, causing unintended write failure status when checking iocb->ki_write_stream > max_write_streams in the block device. Let's just use kzalloc_flex when allocating the aio_cmd and let ki_write_stream=0 to fix this issue.
02KernelScan AI Analysis
Risk summary
SCSI target subsystem fails to initialize ki_write_stream field in aio_cmd structures, causing write operations to fail with bogus stream values. This affects storage systems using SCSI target framework with file-backed LUNs, potentially causing data availability issues.
Vulnerability analysis
The vulnerability occurs because kmalloc_flex() allocates uninitialized memory for aio_cmd structures, leaving the ki_write_stream field with garbage values. When fd_execute_rw_aio() executes write commands, the uninitialized ki_write_stream may exceed max_write_streams limits in block devices, causing legitimate write operations to fail. The fix replaces kmalloc_flex() with kzalloc_flex() to zero-initialize the structure, ensuring ki_write_stream starts at 0. This vulnerability is reachable via network-facing SCSI transports such as iSCSI, allowing remote attackers to cause denial of service by issuing SCSI write commands.
03Fix Versions
| Branch | Fixed in | Patch commit |
|---|---|---|
| 6.18 | 6.18.22 | ce54802fe6bb |
| 6.19 | 6.19.12 | 4eaff1728d0e |
| mainline | 7.0 | 01f784fc9d0a |