CVE-2026-74557scsi: libiscsi: Fix stale-data leak into the SCSI sense buffer

Official description

In the Linux kernel, the following vulnerability has been resolved: scsi: libiscsi: Fix stale-data leak into the SCSI sense buffer iscsi_scsi_cmd_rsp() copies the sense data of a SCSI Response from the target-supplied data segment. The segment carries a 2-byte sense length followed by the sense bytes, so it must hold 2 + senselen bytes, but the bounds check only requires datalen >= senselen: senselen = get_unaligned_be16(data); if (datalen < senselen) goto invalid_datalen; memcpy(sc->sense_buffer, data + 2, min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE)); A target that returns a SCSI Response whose datalen equals senselen (with senselen <= SCSI_SENSE_BUFFERSIZE) makes the memcpy() from data + 2 read up to two bytes past the received data. Those bytes are stale conn->data contents and end up in the command's sense buffer, which is returned to userspace. Account for the 2-byte sense length prefix in the check.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/812f1ae95b22419422972748f173b0916ee4d621
• https://git.kernel.org/stable/c/fef6167e8149896cd81bea333fd51b1c91239149
• https://git.kernel.org/stable/c/baa04572673125e4d5bc309b4077d1cb46cc78d1
• https://git.kernel.org/stable/c/7567f06abdefb1caf2d836107c4d08c5185c650e
• https://git.kernel.org/stable/c/60499924faf4ef97e84228c20515218ef121facf
• https://git.kernel.org/stable/c/3ef209ca0b4b68c75e9a814d90cc916026b5a6ac
• https://git.kernel.org/stable/c/1f07a897d43c63e6c9458bf77450defef39b5833
• https://git.kernel.org/stable/c/98b87885de4b7f605533a2860685f5689fce8e82