{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nata: pata_macio: Fix DMA table overflow\n\nKolbjørn and Jonáš reported that their 32-bit PowerMacs were crashing\nin pata-macio since commit 09fe2bfa6b83 (\"ata: pata_macio: Fix\nmax_segment_size with PAGE_SIZE == 64K\").\n\nFor example:\n\n  kernel BUG at drivers/ata/pata_macio.c:544!\n  Oops: Exception in kernel mode, sig: 5 [#1]\n  BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 DEBUG_PAGEALLOC PowerMac\n  ...\n  NIP pata_macio_qc_prep+0xf4/0x190\n  LR  pata_macio_qc_prep+0xfc/0x190\n  Call Trace:\n    0xc1421660 (unreliable)\n    ata_qc_issue+0x14c/0x2d4\n    __ata_scsi_queuecmd+0x200/0x53c\n    ata_scsi_queuecmd+0x50/0xe0\n    scsi_queue_rq+0x788/0xb1c\n    __blk_mq_issue_directly+0x58/0xf4\n    blk_mq_plug_issue_direct+0x8c/0x1b4\n    blk_mq_flush_plug_list.part.0+0x584/0x5e0\n    __blk_flush_plug+0xf8/0x194\n    __submit_bio+0x1b8/0x2e0\n    submit_bio_noacct_nocheck+0x230/0x304\n    btrfs_work_helper+0x200/0x338\n    process_one_work+0x1a8/0x338\n    worker_thread+0x364/0x4c0\n    kthread+0x100/0x104\n    start_kernel_thread+0x10/0x14\n\nThat commit increased max_segment_size to 64KB, with the justification\nthat the SCSI core was already using that size when PAGE_SIZE == 64KB,\nand that there was existing logic to split over-sized requests.\n\nHowever with a sufficiently large request, the splitting logic causes\neach sg to be split into two commands in the DMA table, leading to\noverflow of the DMA table, triggering the BUG_ON().\n\nWith default settings the bug doesn't trigger, because the request size\nis limited by max_sectors_kb == 1280, however max_sectors_kb can be\nincreased, and apparently some distros do that by default using udev\nrules.\n\nFix the bug for 4KB kernels by reverting to the old max_segment_size.\n\nFor 64KB kernels the sg_tablesize needs to be halved, to allow for the\npossibility that each sg will be split into two."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "drivers/ata/pata_macio.c"
               ],
               "versions": [
                  {
                     "version": "09fe2bfa6b83",
                     "lessThan": "709e4c8f78e1",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "09fe2bfa6b83",
                     "lessThan": "822c8020aebc",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "drivers/ata/pata_macio.c"
               ],
               "versions": [
                  {
                     "version": "6.10",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "6.10",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.10.7",
                     "lessThanOrEqual": "6.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.11",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/709e4c8f78e156ab332297bdd87527ec3da4e2d4"
            },
            {
               "url": "https://git.kernel.org/stable/c/822c8020aebcf5804a143b891e34f29873fee5e2"
            }
         ],
         "title": "ata: pata_macio: Fix DMA table overflow",
         "x_generator": {
            "engine": "bippy-c9c4e1df01b2"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2024-44976",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}