{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64: entry: always set GIC_PRIO_PSR_I_SET during entry\n\nZenghui reports that booting a kernel with \"irqchip.gicv3_pseudo_nmi=1\"\non the command line hits a warning during kernel entry, due to the way\nwe manipulate the PMR.\n\nEarly in the entry sequence, we call lockdep_hardirqs_off() to inform\nlockdep that interrupts have been masked (as the HW sets DAIF wqhen\nentering an exception). Architecturally PMR_EL1 is not affected by\nexception entry, and we don't set GIC_PRIO_PSR_I_SET in the PMR early in\nthe exception entry sequence, so early in exception entry the PMR can\nindicate that interrupts are unmasked even though they are masked by\nDAIF.\n\nIf DEBUG_LOCKDEP is selected, lockdep_hardirqs_off() will check that\ninterrupts are masked, before we set GIC_PRIO_PSR_I_SET in any of the\nexception entry paths, and hence lockdep_hardirqs_off() will WARN() that\nsomething is amiss.\n\nWe can avoid this by consistently setting GIC_PRIO_PSR_I_SET during\nexception entry so that kernel code sees a consistent environment. We\nmust also update local_daif_inherit() to undo this, as currently only\ntouches DAIF. For other paths, local_daif_restore() will update both\nDAIF and the PMR. With this done, we can remove the existing special\ncases which set this later in the entry code.\n\nWe always use (GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET) for consistency with\nlocal_daif_save(), as this will warn if it ever encounters\n(GIC_PRIO_IRQOFF | GIC_PRIO_PSR_I_SET), and never sets this itself. This\nmatches the gic_prio_kentry_setup that we have to retain for\nret_to_user.\n\nThe original splat from Zenghui's report was:\n\n| DEBUG_LOCKS_WARN_ON(!irqs_disabled())\n| WARNING: CPU: 3 PID: 125 at kernel/locking/lockdep.c:4258 lockdep_hardirqs_off+0xd4/0xe8\n| Modules linked in:\n| CPU: 3 PID: 125 Comm: modprobe Tainted: G        W         5.12.0-rc8+ #463\n| Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015\n| pstate: 604003c5 (nZCv DAIF +PAN -UAO -TCO BTYPE=--)\n| pc : lockdep_hardirqs_off+0xd4/0xe8\n| lr : lockdep_hardirqs_off+0xd4/0xe8\n| sp : ffff80002a39bad0\n| pmr_save: 000000e0\n| x29: ffff80002a39bad0 x28: ffff0000de214bc0\n| x27: ffff0000de1c0400 x26: 000000000049b328\n| x25: 0000000000406f30 x24: ffff0000de1c00a0\n| x23: 0000000020400005 x22: ffff8000105f747c\n| x21: 0000000096000044 x20: 0000000000498ef9\n| x19: ffff80002a39bc88 x18: ffffffffffffffff\n| x17: 0000000000000000 x16: ffff800011c61eb0\n| x15: ffff800011700a88 x14: 0720072007200720\n| x13: 0720072007200720 x12: 0720072007200720\n| x11: 0720072007200720 x10: 0720072007200720\n| x9 : ffff80002a39bad0 x8 : ffff80002a39bad0\n| x7 : ffff8000119f0800 x6 : c0000000ffff7fff\n| x5 : ffff8000119f07a8 x4 : 0000000000000001\n| x3 : 9bcdab23f2432800 x2 : ffff800011730538\n| x1 : 9bcdab23f2432800 x0 : 0000000000000000\n| Call trace:\n|  lockdep_hardirqs_off+0xd4/0xe8\n|  enter_from_kernel_mode.isra.5+0x7c/0xa8\n|  el1_abort+0x24/0x100\n|  el1_sync_handler+0x80/0xd0\n|  el1_sync+0x6c/0x100\n|  __arch_clear_user+0xc/0x90\n|  load_elf_binary+0x9fc/0x1450\n|  bprm_execve+0x404/0x880\n|  kernel_execve+0x180/0x188\n|  call_usermodehelper_exec_async+0xdc/0x158\n|  ret_from_fork+0x10/0x18"
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "arch/arm64/include/asm/daifflags.h",
                  "arch/arm64/kernel/entry-common.c",
                  "arch/arm64/kernel/entry.S"
               ],
               "versions": [
                  {
                     "version": "2a9b3e6ac69a",
                     "lessThan": "51524fa8b5f7",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "2a9b3e6ac69a",
                     "lessThan": "e67a83f07800",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "2a9b3e6ac69a",
                     "lessThan": "d8d52005f57b",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "2a9b3e6ac69a",
                     "lessThan": "4d6a38da8e79",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "arch/arm64/include/asm/daifflags.h",
                  "arch/arm64/kernel/entry-common.c",
                  "arch/arm64/kernel/entry.S"
               ],
               "versions": [
                  {
                     "version": "5.10",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.10",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.10.38",
                     "lessThanOrEqual": "5.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.11.22",
                     "lessThanOrEqual": "5.11.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.12.5",
                     "lessThanOrEqual": "5.12.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.13",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/51524fa8b5f7b879ba569227738375d283b79382"
            },
            {
               "url": "https://git.kernel.org/stable/c/e67a83f078005461b59b4c776e6b5addd11725fa"
            },
            {
               "url": "https://git.kernel.org/stable/c/d8d52005f57bbb4a4ec02f647e2555d327135c68"
            },
            {
               "url": "https://git.kernel.org/stable/c/4d6a38da8e79e94cbd1344aa90876f0f805db705"
            }
         ],
         "title": "arm64: entry: always set GIC_PRIO_PSR_I_SET during entry",
         "x_generator": {
            "engine": "bippy-a5840b7849dd"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-46997",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}
