{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2021-47114",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: fix data corruption by fallocate\n\nWhen fallocate punches holes out of inode size, if original isize is in\nthe middle of last cluster, then the part from isize to the end of the\ncluster will be zeroed with buffer write, at that time isize is not yet\nupdated to match the new size, if writeback is kicked in, it will invoke\nocfs2_writepage()->block_write_full_page() where the pages out of inode\nsize will be dropped.  That will cause file corruption.  Fix this by\nzero out eof blocks when extending the inode size.\n\nRunning the following command with qemu-image 4.2.1 can get a corrupted\ncoverted image file easily.\n\n    qemu-img convert -p -t none -T none -f qcow2 $qcow_image \\\n             -O qcow2 -o compat=1.1 $qcow_image.conv\n\nThe usage of fallocate in qemu is like this, it first punches holes out\nof inode size, then extend the inode size.\n\n    fallocate(11, FALLOC_FL_KEEP_SIZE|FALLOC_FL_PUNCH_HOLE, 2276196352, 65536) = 0\n    fallocate(11, 0, 2276196352, 65536) = 0\n\nv1: https://www.spinics.net/lists/linux-fsdevel/msg193999.html\nv2: https://lore.kernel.org/linux-fsdevel/20210525093034.GB4112@quack2.suse.cz/T/"
            }
        ]
    },
    "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": "1da177e4c3f4",
                                            "version_value": "624fa7baa378"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "4.4.272",
                                                        "lessThanOrEqual": "4.4.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "4.9.272",
                                                        "lessThanOrEqual": "4.9.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "4.14.236",
                                                        "lessThanOrEqual": "4.14.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "4.19.194",
                                                        "lessThanOrEqual": "4.19.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.4.125",
                                                        "lessThanOrEqual": "5.4.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.10.43",
                                                        "lessThanOrEqual": "5.10.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.12.10",
                                                        "lessThanOrEqual": "5.12.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.13",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
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                                                "defaultStatus": "affected"
                                            }
                                        }
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    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/624fa7baa3788dc9e57840ba5b94bc22b03cda57",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/624fa7baa3788dc9e57840ba5b94bc22b03cda57"
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                "url": "https://git.kernel.org/stable/c/33e03adafb29eedae1bae9cdb50c1385279fcf65",
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                "name": "https://git.kernel.org/stable/c/33e03adafb29eedae1bae9cdb50c1385279fcf65"
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            {
                "url": "https://git.kernel.org/stable/c/a1700479524bb9cb5e8ae720236a6fabd003acae",
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                "name": "https://git.kernel.org/stable/c/a1700479524bb9cb5e8ae720236a6fabd003acae"
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                "name": "https://git.kernel.org/stable/c/cec4e857ffaa8c447f51cd8ab4e72350077b6770"
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                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/cc2edb99ea606a45182b5ea38cc8f4e583aa0774"
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                "name": "https://git.kernel.org/stable/c/c8d5faee46242c3f33b8a71a4d7d52214785bfcc"
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                "url": "https://git.kernel.org/stable/c/0a31dd6fd2f4e7db538fb6eb1f06973d81f8dd3b",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/0a31dd6fd2f4e7db538fb6eb1f06973d81f8dd3b"
            },
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                "url": "https://git.kernel.org/stable/c/6bba4471f0cc1296fe3c2089b9e52442d3074b2e",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/6bba4471f0cc1296fe3c2089b9e52442d3074b2e"
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