CVE-2023-54069
ext4: fix BUG in ext4_mb_new_inode_pa() due to overflow
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: ext4: fix BUG in ext4_mb_new_inode_pa() due to overflow When we calculate the end position of ext4_free_extent, this position may be exactly where ext4_lblk_t (i.e. uint) overflows. For example, if ac_g_ex.fe_logical is 4294965248 and ac_orig_goal_len is 2048, then the computed end is 0x100000000, which is 0. If ac->ac_o_ex.fe_logical is not the first case of adjusting the best extent, that is, new_bex_end > 0, the following BUG_ON will be triggered: ========================================================= kernel BUG at fs/ext4/mballoc.c:5116! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 3 PID: 673 Comm: xfs_io Tainted: G E 6.5.0-rc1+ #279 RIP: 0010:ext4_mb_new_inode_pa+0xc5/0x430 Call Trace: <TASK> ext4_mb_use_best_found+0x203/0x2f0 ext4_mb_try_best_found+0x163/0x240 ext4_mb_regular_allocator+0x158/0x1550 ext4_mb_new_blocks+0x86a/0xe10 ext4_ext_map_blocks+0xb0c/0x13a0 ext4_map_blocks+0x2cd/0x8f0 ext4_iomap_begin+0x27b/0x400 iomap_iter+0x222/0x3d0 __iomap_dio_rw+0x243/0xcb0 iomap_dio_rw+0x16/0x80 ========================================================= A simple reproducer demonstrating the problem: mkfs.ext4 -F /dev/sda -b 4096 100M mount /dev/sda /tmp/test fallocate -l1M /tmp/test/tmp fallocate -l10M /tmp/test/file fallocate -i -o 1M -l16777203M /tmp/test/file fsstress -d /tmp/test -l 0 -n 100000 -p 8 & sleep 10 && killall -9 fsstress rm -f /tmp/test/tmp xfs_io -c "open -ad /tmp/test/file" -c "pwrite -S 0xff 0 8192" We simply refactor the logic for adjusting the best extent by adding a temporary ext4_free_extent ex and use extent_logical_end() to avoid overflow, which also simplifies the code.
Timeline
ID reserved
By Linux
Published
- 5 months later
· 5 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Deferred.
- EPSS (exploitation in 30 days)
- 0.21% · top 89% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected 8659c5f4ffaacbe932849b98462c3d635b4eacea – < 83ecffd40c65844a73c2e93d7c841455786605ac
- affected fc7237e191b99f88e859316fab2b06c2c26c8344 – < 58fe961c606c446f5612f6897827b1cac42c2e89
- affected 613f6cde5ebb005a37fda117cdda7b4126170c13 – < f2c3a3aa6f11ad9878dbc3a067b0633e07b586c1
- affected 9d4430b7f862ce8835ca4e054b6916d15c8e0862 – < fcefddf3a151b2c416b20120c06bb1ba9ad676fb
- affected 93cdf49f6eca5e23f6546b8f28457b2e6a6961d9 – < b7e9ec38b6a0beb5a49cd1e76be0a9a07c218e90
- affected 93cdf49f6eca5e23f6546b8f28457b2e6a6961d9 – < bc056e7163ac7db945366de219745cf94f32a3e6
- affected 46772ab99409cc72241227dd8f5295f358233fda
- affected 25a60b4533268477920faaeebd99e7e69c0735cd
- affected cec4ef62b36b04e0bc8905732adab091f4bc1cfd
- affected 5.4.244 – < 5.4.260
- affected 5.10.181 – < 5.10.200
- affected 5.15.113 – < 5.15.138
- affected 6.1.30 – < 6.1.61
- affected 4.14.316 – < 4.15
- affected 4.19.284 – < 4.20
- affected 6.3.4 – < 6.4
- affected 6.4
- unaffected < 6.4
- unaffected 5.4.260 – ≤ 5.4.*
- unaffected 5.10.200 – ≤ 5.10.*
- unaffected 5.15.138 – ≤ 5.15.*
- unaffected 6.1.61 – ≤ 6.1.*
- unaffected 6.5.5 – ≤ 6.5.*
- unaffected 6.6 – ≤ *
References (6)
- https://git.kernel.org/stable/c/83ecffd40c65844a73c2e93d7c841455786605ac (opens in a new tab)
- https://git.kernel.org/stable/c/58fe961c606c446f5612f6897827b1cac42c2e89 (opens in a new tab)
- https://git.kernel.org/stable/c/f2c3a3aa6f11ad9878dbc3a067b0633e07b586c1 (opens in a new tab)
- https://git.kernel.org/stable/c/fcefddf3a151b2c416b20120c06bb1ba9ad676fb (opens in a new tab)
- https://git.kernel.org/stable/c/b7e9ec38b6a0beb5a49cd1e76be0a9a07c218e90 (opens in a new tab)
- https://git.kernel.org/stable/c/bc056e7163ac7db945366de219745cf94f32a3e6 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://trackcve.app/cve/CVE-2023-54069)Record last updated .