{"cve":"CVE-2023-54069","nvd":{"published":"2025-12-24T13:16:08.747","modified":"2026-06-17T06:46:44.757","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix BUG in ext4_mb_new_inode_pa() due to overflow\n\nWhen we calculate the end position of ext4_free_extent, this position may\nbe exactly where ext4_lblk_t (i.e. uint) overflows. For example, if\nac_g_ex.fe_logical is 4294965248 and ac_orig_goal_len is 2048, then the\ncomputed end is 0x100000000, which is 0. If ac->ac_o_ex.fe_logical is not\nthe first case of adjusting the best extent, that is, new_bex_end > 0, the\nfollowing BUG_ON will be triggered:\n\n=========================================================\nkernel BUG at fs/ext4/mballoc.c:5116!\ninvalid opcode: 0000 [#1] PREEMPT SMP PTI\nCPU: 3 PID: 673 Comm: xfs_io Tainted: G E 6.5.0-rc1+ #279\nRIP: 0010:ext4_mb_new_inode_pa+0xc5/0x430\nCall Trace:\n <TASK>\n ext4_mb_use_best_found+0x203/0x2f0\n ext4_mb_try_best_found+0x163/0x240\n ext4_mb_regular_allocator+0x158/0x1550\n ext4_mb_new_blocks+0x86a/0xe10\n ext4_ext_map_blocks+0xb0c/0x13a0\n ext4_map_blocks+0x2cd/0x8f0\n ext4_iomap_begin+0x27b/0x400\n iomap_iter+0x222/0x3d0\n __iomap_dio_rw+0x243/0xcb0\n iomap_dio_rw+0x16/0x80\n=========================================================\n\nA simple reproducer demonstrating the problem:\n\n\tmkfs.ext4 -F /dev/sda -b 4096 100M\n\tmount /dev/sda /tmp/test\n\tfallocate -l1M /tmp/test/tmp\n\tfallocate -l10M /tmp/test/file\n\tfallocate -i -o 1M -l16777203M /tmp/test/file\n\tfsstress -d /tmp/test -l 0 -n 100000 -p 8 &\n\tsleep 10 && killall -9 fsstress\n\trm -f /tmp/test/tmp\n\txfs_io -c \"open -ad /tmp/test/file\" -c \"pwrite -S 0xff 0 8192\"\n\nWe simply refactor the logic for adjusting the best extent by adding\na temporary ext4_free_extent ex and use extent_logical_end() to avoid\noverflow, which also simplifies the code.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/58fe961c606c446f5612f6897827b1cac42c2e89","https://git.kernel.org/stable/c/83ecffd40c65844a73c2e93d7c841455786605ac","https://git.kernel.org/stable/c/b7e9ec38b6a0beb5a49cd1e76be0a9a07c218e90","https://git.kernel.org/stable/c/bc056e7163ac7db945366de219745cf94f32a3e6","https://git.kernel.org/stable/c/f2c3a3aa6f11ad9878dbc3a067b0633e07b586c1"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:18:08.089039631+00:00"},"epss":{"cve":"CVE-2023-54069","score":0.00209,"percentile":0.11132,"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."]}