{"id":"CVE-2026-98127","revision":"398c37b18eef45da9b138d6b0da2b21f","records":[{"revision":"398c37b18eef45da9b138d6b0da2b21f","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98127","aliases":[],"title":"smb/client: validate new EOF for insert range","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: validate new EOF for insert range\n\nsmb3_insert_range() does not check if the new file size\n(i_size + len) is valid. This allows FALLOC_FL_INSERT_RANGE to bypass\nRLIMIT_FSIZE, exceed s_maxbytes, or produce a size outside the loff_t\nrange.\n\nUse check_add_overflow() to calculate the new EOF. Validate it with\ninode_newsize_ok() before modifying the file.\n\nReproducer, using a file on a CIFS mount:\n\n\tbash -c '\n\t\tFILE=/mnt/cifs/repro\n\n\t\ttrap \"\" SIGXFSZ\n\t\tulimit -f 3072\t\t# RLIMIT_FSIZE = 3 MiB\n\n\t\t# A regular write is stopped at 3 MiB.\n\t\tdd if=/dev/zero of=\"$FILE\" bs=1M count=4 status=none\n\t\tstat -c \"size after write: %s\" \"$FILE\"\n\n\t\t# Insert 2 MiB into a 2 MiB file.\n\t\ttruncate -s 2M \"$FILE\"\n\t\tfallocate -i -o 0 -l 2M \"$FILE\"\n\t\tstat -c \"size after insert: %s\" \"$FILE\"\n\t'\n\nBefore this change, the regular write stops at the 3 MiB limit, but\ninsert range grows the file to 4 MiB:\n\n\tdd: error writing '/mnt/cifs/repro': File too large\n\tsize after write: 3145728\n\tsize after insert: 4194304\n\nAfter this change, insert range also fails at the limit and leaves the\n2 MiB file unchanged:\n\n\tdd: error writing '/mnt/cifs/repro': File too large\n\tsize after write: 3145728\n\tfallocate: fallocate failed: File too large\n\tsize after insert: 2097152","state":0,"publishedAt":"2026-09-25T10:36:08.406+00:00","modifiedAt":"2026-10-21T12:54:38.54+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/smb/client/smb2ops.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7fe6fe95b936084dce6eedcc2cccadf96eafae73\",\n                            \"lessThan\": \"b7f2e33d9f5db7b8e6e5e0a5a93d0c5e31870356\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"7fe6fe95b936084dce6eedcc2cccadf96eafae73\",\n                            \"lessThan\": \"7c2c69045aa76ccaa7f16f1478eb312130ce4951\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"7fe6fe95b936084dce6eedcc2cccadf96eafae73\",\n                            \"lessThan\": \"bc7602b9082ef195d913c4c16fa9853dd262333e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"7fe6fe95b936084dce6eedcc2cccadf96eafae73\",\n                            \"lessThan\": \"f8cbfe3a3fcee7d991fd223f660f3e5df13221cf\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"7fe6fe95b936084dce6eedcc2cccadf96eafae73\",\n                            \"lessThan\": \"1519dc88c87f5346dae0464d7d6da1b6bf1f6e8e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/smb/client/smb2ops.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5.13\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"5.13\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.160\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.111\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.53\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.7\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/b7f2e33d9f5db7b8e6e5e0a5a93d0c5e31870356","https://git.kernel.org/stable/c/7c2c69045aa76ccaa7f16f1478eb312130ce4951","https://git.kernel.org/stable/c/bc7602b9082ef195d913c4c16fa9853dd262333e","https://git.kernel.org/stable/c/f8cbfe3a3fcee7d991fd223f660f3e5df13221cf","https://git.kernel.org/stable/c/1519dc88c87f5346dae0464d7d6da1b6bf1f6e8e"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98127","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98127","identifiers":["CVE-2026-98127"]},"retained":false,"historicalAffected":[]}],"coverage":[]}