{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-40914",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/huge_memory: don't unpoison huge_zero_folio\n\nWhen I did memory failure tests recently, below panic occurs:\n\n kernel BUG at include/linux/mm.h:1135!\n invalid opcode: 0000 [#1] PREEMPT SMP NOPTI\n CPU: 9 PID: 137 Comm: kswapd1 Not tainted 6.9.0-rc4-00491-gd5ce28f156fe-dirty #14\n RIP: 0010:shrink_huge_zero_page_scan+0x168/0x1a0\n RSP: 0018:ffff9933c6c57bd0 EFLAGS: 00000246\n RAX: 000000000000003e RBX: 0000000000000000 RCX: ffff88f61fc5c9c8\n RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff88f61fc5c9c0\n RBP: ffffcd7c446b0000 R08: ffffffff9a9405f0 R09: 0000000000005492\n R10: 00000000000030ea R11: ffffffff9a9405f0 R12: 0000000000000000\n R13: 0000000000000000 R14: 0000000000000000 R15: ffff88e703c4ac00\n FS:  0000000000000000(0000) GS:ffff88f61fc40000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000055f4da6e9878 CR3: 0000000c71048000 CR4: 00000000000006f0\n Call Trace:\n  <TASK>\n  do_shrink_slab+0x14f/0x6a0\n  shrink_slab+0xca/0x8c0\n  shrink_node+0x2d0/0x7d0\n  balance_pgdat+0x33a/0x720\n  kswapd+0x1f3/0x410\n  kthread+0xd5/0x100\n  ret_from_fork+0x2f/0x50\n  ret_from_fork_asm+0x1a/0x30\n  </TASK>\n Modules linked in: mce_inject hwpoison_inject\n ---[ end trace 0000000000000000 ]---\n RIP: 0010:shrink_huge_zero_page_scan+0x168/0x1a0\n RSP: 0018:ffff9933c6c57bd0 EFLAGS: 00000246\n RAX: 000000000000003e RBX: 0000000000000000 RCX: ffff88f61fc5c9c8\n RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff88f61fc5c9c0\n RBP: ffffcd7c446b0000 R08: ffffffff9a9405f0 R09: 0000000000005492\n R10: 00000000000030ea R11: ffffffff9a9405f0 R12: 0000000000000000\n R13: 0000000000000000 R14: 0000000000000000 R15: ffff88e703c4ac00\n FS:  0000000000000000(0000) GS:ffff88f61fc40000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000055f4da6e9878 CR3: 0000000c71048000 CR4: 00000000000006f0\n\nThe root cause is that HWPoison flag will be set for huge_zero_folio\nwithout increasing the folio refcnt.  But then unpoison_memory() will\ndecrease the folio refcnt unexpectedly as it appears like a successfully\nhwpoisoned folio leading to VM_BUG_ON_PAGE(page_ref_count(page) == 0) when\nreleasing huge_zero_folio.\n\nSkip unpoisoning huge_zero_folio in unpoison_memory() to fix this issue. \nWe're not prepared to unpoison huge_zero_folio yet."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "f8f836100fff",
                                            "version_value": "688bb46ad339"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "478d134e9506",
                                            "version_value": "b2494506f306"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.18",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "5.18",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.15.162",
                                                        "lessThanOrEqual": "5.15.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.1.95",
                                                        "lessThanOrEqual": "6.1.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.6.35",
                                                        "lessThanOrEqual": "6.6.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.9.6",
                                                        "lessThanOrEqual": "6.9.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.10",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
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    "references": {
        "reference_data": [
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                "url": "https://git.kernel.org/stable/c/688bb46ad339497b5b7f527b6636d2afe04b46af",
                "refsource": "MISC",
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                "url": "https://git.kernel.org/stable/c/b2494506f30675245a3e6787281f79601af087bf",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/b2494506f30675245a3e6787281f79601af087bf"
            },
            {
                "url": "https://git.kernel.org/stable/c/0d73477af964dbd7396163a13817baf13940bca9",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/0d73477af964dbd7396163a13817baf13940bca9"
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                "url": "https://git.kernel.org/stable/c/d72b7711919de49d92a67dfc844a6cf4c23dd794",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/d72b7711919de49d92a67dfc844a6cf4c23dd794"
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                "url": "https://git.kernel.org/stable/c/fe6f86f4b40855a130a19aa589f9ba7f650423f4",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/fe6f86f4b40855a130a19aa589f9ba7f650423f4"
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