{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nima: Avoid blocking in RCU read-side critical section\n\nA panic happens in ima_match_policy:\n\nBUG: unable to handle kernel NULL pointer dereference at 0000000000000010\nPGD 42f873067 P4D 0\nOops: 0000 [#1] SMP NOPTI\nCPU: 5 PID: 1286325 Comm: kubeletmonit.sh\nKdump: loaded Tainted: P\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996),\n               BIOS 0.0.0 02/06/2015\nRIP: 0010:ima_match_policy+0x84/0x450\nCode: 49 89 fc 41 89 cf 31 ed 89 44 24 14 eb 1c 44 39\n      7b 18 74 26 41 83 ff 05 74 20 48 8b 1b 48 3b 1d\n      f2 b9 f4 00 0f 84 9c 01 00 00 <44> 85 73 10 74 ea\n      44 8b 6b 14 41 f6 c5 01 75 d4 41 f6 c5 02 74 0f\nRSP: 0018:ff71570009e07a80 EFLAGS: 00010207\nRAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000200\nRDX: ffffffffad8dc7c0 RSI: 0000000024924925 RDI: ff3e27850dea2000\nRBP: 0000000000000000 R08: 0000000000000000 R09: ffffffffabfce739\nR10: ff3e27810cc42400 R11: 0000000000000000 R12: ff3e2781825ef970\nR13: 00000000ff3e2785 R14: 000000000000000c R15: 0000000000000001\nFS:  00007f5195b51740(0000)\nGS:ff3e278b12d40000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000000000000010 CR3: 0000000626d24002 CR4: 0000000000361ee0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n ima_get_action+0x22/0x30\n process_measurement+0xb0/0x830\n ? page_add_file_rmap+0x15/0x170\n ? alloc_set_pte+0x269/0x4c0\n ? prep_new_page+0x81/0x140\n ? simple_xattr_get+0x75/0xa0\n ? selinux_file_open+0x9d/0xf0\n ima_file_check+0x64/0x90\n path_openat+0x571/0x1720\n do_filp_open+0x9b/0x110\n ? page_counter_try_charge+0x57/0xc0\n ? files_cgroup_alloc_fd+0x38/0x60\n ? __alloc_fd+0xd4/0x250\n ? do_sys_open+0x1bd/0x250\n do_sys_open+0x1bd/0x250\n do_syscall_64+0x5d/0x1d0\n entry_SYSCALL_64_after_hwframe+0x65/0xca\n\nCommit c7423dbdbc9e (\"ima: Handle -ESTALE returned by\nima_filter_rule_match()\") introduced call to ima_lsm_copy_rule within a\nRCU read-side critical section which contains kmalloc with GFP_KERNEL.\nThis implies a possible sleep and violates limitations of RCU read-side\ncritical sections on non-PREEMPT systems.\n\nSleeping within RCU read-side critical section might cause\nsynchronize_rcu() returning early and break RCU protection, allowing a\nUAF to happen.\n\nThe root cause of this issue could be described as follows:\n|\tThread A\t|\tThread B\t|\n|\t\t\t|ima_match_policy\t|\n|\t\t\t|  rcu_read_lock\t|\n|ima_lsm_update_rule\t|\t\t\t|\n|  synchronize_rcu\t|\t\t\t|\n|\t\t\t|    kmalloc(GFP_KERNEL)|\n|\t\t\t|      sleep\t\t|\n==> synchronize_rcu returns early\n|  kfree(entry)\t\t|\t\t\t|\n|\t\t\t|    entry = entry->next|\n==> UAF happens and entry now becomes NULL (or could be anything).\n|\t\t\t|    entry->action\t|\n==> Accessing entry might cause panic.\n\nTo fix this issue, we are converting all kmalloc that is called within\nRCU read-side critical section to use GFP_ATOMIC.\n\n[PM: fixed missing comment, long lines, !CONFIG_IMA_LSM_RULES case]"
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "include/linux/lsm_hook_defs.h",
                  "include/linux/security.h",
                  "kernel/auditfilter.c",
                  "security/apparmor/audit.c",
                  "security/apparmor/include/audit.h",
                  "security/integrity/ima/ima.h",
                  "security/integrity/ima/ima_policy.c",
                  "security/security.c",
                  "security/selinux/include/audit.h",
                  "security/selinux/ss/services.c",
                  "security/smack/smack_lsm.c"
               ],
               "versions": [
                  {
                     "version": "c4b035b1f036",
                     "lessThan": "a6176a802c4b",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "2d4bc60693c4",
                     "lessThan": "a38e02265c68",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "8008f1691c15",
                     "lessThan": "9c3906c37385",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "c7423dbdbc9e",
                     "lessThan": "28d0ecc52f6c",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "c7423dbdbc9e",
                     "lessThan": "582754558930",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "c7423dbdbc9e",
                     "lessThan": "9a95c5bfbf02",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "include/linux/lsm_hook_defs.h",
                  "include/linux/security.h",
                  "kernel/auditfilter.c",
                  "security/apparmor/audit.c",
                  "security/apparmor/include/audit.h",
                  "security/integrity/ima/ima.h",
                  "security/integrity/ima/ima_policy.c",
                  "security/security.c",
                  "security/selinux/include/audit.h",
                  "security/selinux/ss/services.c",
                  "security/smack/smack_lsm.c"
               ],
               "versions": [
                  {
                     "version": "6.2",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "6.2",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.10.222",
                     "lessThanOrEqual": "5.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15.163",
                     "lessThanOrEqual": "5.15.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.1.98",
                     "lessThanOrEqual": "6.1.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.6.39",
                     "lessThanOrEqual": "6.6.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.9.7",
                     "lessThanOrEqual": "6.9.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.10",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/a6176a802c4bfb83bf7524591aa75f44a639a853"
            },
            {
               "url": "https://git.kernel.org/stable/c/a38e02265c681b51997a264aaf743095e2ee400a"
            },
            {
               "url": "https://git.kernel.org/stable/c/9c3906c3738562b1fedc6f1cfc81756a7cfefff0"
            },
            {
               "url": "https://git.kernel.org/stable/c/28d0ecc52f6c927d0e9ba70a4f2c1ea15453ee88"
            },
            {
               "url": "https://git.kernel.org/stable/c/58275455893066149e9f4df2223ab2fdbdc59f9c"
            },
            {
               "url": "https://git.kernel.org/stable/c/9a95c5bfbf02a0a7f5983280fe284a0ff0836c34"
            }
         ],
         "title": "ima: Avoid blocking in RCU read-side critical section",
         "x_generator": {
            "engine": "bippy-c9c4e1df01b2"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2024-40947",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}
