{"cve":"CVE-2023-53513","nvd":{"published":"2025-10-01T12:15:55.317","modified":"2026-06-17T06:45:30.400","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnbd: fix incomplete validation of ioctl arg\n\nWe tested and found an alarm caused by nbd_ioctl arg without verification.\nThe UBSAN warning calltrace like below:\n\nUBSAN: Undefined behaviour in fs/buffer.c:1709:35\nsigned integer overflow:\n-9223372036854775808 - 1 cannot be represented in type 'long long int'\nCPU: 3 PID: 2523 Comm: syz-executor.0 Not tainted 4.19.90 #1\nHardware name: linux,dummy-virt (DT)\nCall trace:\n dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78\n show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158\n __dump_stack lib/dump_stack.c:77 [inline]\n dump_stack+0x170/0x1dc lib/dump_stack.c:118\n ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161\n handle_overflow+0x188/0x1dc lib/ubsan.c:192\n __ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:206\n __block_write_full_page+0x94c/0xa20 fs/buffer.c:1709\n block_write_full_page+0x1f0/0x280 fs/buffer.c:2934\n blkdev_writepage+0x34/0x40 fs/block_dev.c:607\n __writepage+0x68/0xe8 mm/page-writeback.c:2305\n write_cache_pages+0x44c/0xc70 mm/page-writeback.c:2240\n generic_writepages+0xdc/0x148 mm/page-writeback.c:2329\n blkdev_writepages+0x2c/0x38 fs/block_dev.c:2114\n do_writepages+0xd4/0x250 mm/page-writeback.c:2344\n\nThe reason for triggering this warning is __block_write_full_page()\n-> i_size_read(inode) - 1 overflow.\ninode->i_size is assigned in __nbd_ioctl() -> nbd_set_size() -> bytesize.\nWe think it is necessary to limit the size of arg to prevent errors.\n\nMoreover, __nbd_ioctl() -> nbd_add_socket(), arg will be cast to int.\nAssuming the value of arg is 0x80000000000000001) (on a 64-bit machine),\nit will become 1 after the coercion, which will return unexpected results.\n\nFix it by adding checks to prevent passing in too large numbers.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-674"],"references":["https://git.kernel.org/stable/c/52851d0c3354b397c11d31dfeb8b2a2fc85a0002","https://git.kernel.org/stable/c/55793ea54d77719a071b1ccc05a05056e3b5e009","https://git.kernel.org/stable/c/fab766c8a1aff715bce7075aab40e780266f8e1a","https://git.kernel.org/stable/c/ffb75ffaa68723276365d0f9d00b03362b750657"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:11:26.888974865+00:00"},"epss":{"cve":"CVE-2023-53513","score":0.00149,"percentile":0.04098,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}