{"cve":"CVE-2023-52622","nvd":{"published":"2024-03-26T18:15:08.873","modified":"2026-10-15T01:17:15.333","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: avoid online resizing failures due to oversized flex bg\n\nWhen we online resize an ext4 filesystem with a oversized flexbg_size,\n\n     mkfs.ext4 -F -G 67108864 $dev -b 4096 100M\n     mount $dev $dir\n     resize2fs $dev 16G\n\nthe following WARN_ON is triggered:\n==================================================================\nWARNING: CPU: 0 PID: 427 at mm/page_alloc.c:4402 __alloc_pages+0x411/0x550\nModules linked in: sg(E)\nCPU: 0 PID: 427 Comm: resize2fs Tainted: G  E  6.6.0-rc5+ #314\nRIP: 0010:__alloc_pages+0x411/0x550\nCall Trace:\n <TASK>\n __kmalloc_large_node+0xa2/0x200\n __kmalloc+0x16e/0x290\n ext4_resize_fs+0x481/0xd80\n __ext4_ioctl+0x1616/0x1d90\n ext4_ioctl+0x12/0x20\n __x64_sys_ioctl+0xf0/0x150\n do_syscall_64+0x3b/0x90\n==================================================================\n\nThis is because flexbg_size is too large and the size of the new_group_data\narray to be allocated exceeds MAX_ORDER. Currently, the minimum value of\nMAX_ORDER is 8, the minimum value of PAGE_SIZE is 4096, the corresponding\nmaximum number of groups that can be allocated is:\n\n (PAGE_SIZE << MAX_ORDER) / sizeof(struct ext4_new_group_data) ≈ 21845\n\nAnd the value that is down-aligned to the power of 2 is 16384. Therefore,\nthis value is defined as MAX_RESIZE_BG, and the number of groups added\neach time does not exceed this value during resizing, and is added multiple\ntimes to complete the online resizing. The difference is that the metadata\nin a flex_bg may be more dispersed.","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-770"],"references":["https://git.kernel.org/stable/c/5d1935ac02ca5aee364a449a35e2977ea84509b0","https://git.kernel.org/stable/c/6d2cbf517dcabc093159cf138ad5712c9c7fa954","https://git.kernel.org/stable/c/8b1413dbfe49646eda2c00c0f1144ee9d3368e0c","https://git.kernel.org/stable/c/b183fe8702e78bba3dcef8e7193cab6898abee07","https://git.kernel.org/stable/c/cd1f93ca97a9136989f3bd2bf90696732a2ed644"],"products":["debian:debian_linux","linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:47:51.568503435+00:00"},"epss":{"cve":"CVE-2023-52622","score":0.00243,"percentile":0.1533,"date":"2026-10-25"},"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."]}