{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-39723",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-04-16T07:20:57.117Z",
        "datePublished": "2025-09-05T17:21:31.137Z",
        "dateUpdated": "2026-07-30T05:57:13.885Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-07-30T05:57:13.885Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix unbuffered write error handling\n\nIf all the subrequests in an unbuffered write stream fail, the subrequest\ncollector doesn't update the stream->transferred value and it retains its\ninitial LONG_MAX value.  Unfortunately, if all active streams fail, then we\ntake the smallest value of { LONG_MAX, LONG_MAX, ... } as the value to set\nin wreq->transferred - which is then returned from ->write_iter().\n\nLONG_MAX was chosen as the initial value so that all the streams can be\nquickly assessed by taking the smallest value of all stream->transferred -\nbut this only works if we've set any of them.\n\nFix this by adding a flag to indicate whether the value in\nstream->transferred is valid and checking that when we integrate the\nvalues.  stream->transferred can then be initialised to zero.\n\nThis was found by running the generic/750 xfstest against cifs with\ncache=none.  It splices data to the target file.  Once (if) it has used up\nall the available scratch space, the writes start failing with ENOSPC.\nThis causes ->write_iter() to fail.  However, it was returning\nwreq->transferred, i.e. LONG_MAX, rather than an error (because it thought\nthe amount transferred was non-zero) and iter_file_splice_write() would\nthen try to clean up that amount of pipe bufferage - leading to an oops\nwhen it overran.  The kernel log showed:\n\n    CIFS: VFS: Send error in write = -28\n\nfollowed by:\n\n    BUG: kernel NULL pointer dereference, address: 0000000000000008\n\nwith:\n\n    RIP: 0010:iter_file_splice_write+0x3a4/0x520\n    do_splice+0x197/0x4e0\n\nor:\n\n    RIP: 0010:pipe_buf_release (include/linux/pipe_fs_i.h:282)\n    iter_file_splice_write (fs/splice.c:755)\n\nAlso put a warning check into splice to announce if ->write_iter() returned\nthat it had written more than it was asked to."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H",
                        "baseScore": 7.1,
                        "baseSeverity": "HIGH"
                    }
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/netfs/read_collect.c",
                        "fs/netfs/write_collect.c",
                        "fs/netfs/write_issue.c",
                        "fs/splice.c",
                        "include/linux/netfs.h"
                    ],
                    "versions": [
                        {
                            "version": "288ace2f57c9d06dd2e42bd80d03747d879a4068",
                            "lessThan": "f08c80af3c9a9849cd178b4843b7c01d103506a1",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "288ace2f57c9d06dd2e42bd80d03747d879a4068",
                            "lessThan": "387164a2b97e1f5404c6d0049a7409bac7d2bc5b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "288ace2f57c9d06dd2e42bd80d03747d879a4068",
                            "lessThan": "a3de58b12ce074ec05b8741fa28d62ccb1070468",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/netfs/read_collect.c",
                        "fs/netfs/write_collect.c",
                        "fs/netfs/write_issue.c",
                        "fs/splice.c",
                        "include/linux/netfs.h"
                    ],
                    "versions": [
                        {
                            "version": "6.10",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.10",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.44",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.16.4",
                            "lessThanOrEqual": "6.16.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.17",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "6.12.44"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "6.16.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "6.17"
                                }
                            ]
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                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/f08c80af3c9a9849cd178b4843b7c01d103506a1"
                },
                {
                    "url": "https://git.kernel.org/stable/c/387164a2b97e1f5404c6d0049a7409bac7d2bc5b"
                },
                {
                    "url": "https://git.kernel.org/stable/c/a3de58b12ce074ec05b8741fa28d62ccb1070468"
                }
            ],
            "title": "netfs: Fix unbuffered write error handling",
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}