lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-ID: <2025050127-CVE-2025-23150-15b8@gregkh> Date: Thu, 1 May 2025 14:56:30 +0200 From: Greg Kroah-Hartman <gregkh@...uxfoundation.org> To: linux-cve-announce@...r.kernel.org Cc: Greg Kroah-Hartman <gregkh@...nel.org> Subject: CVE-2025-23150: ext4: fix off-by-one error in do_split From: Greg Kroah-Hartman <gregkh@...nel.org> Description =========== In the Linux kernel, the following vulnerability has been resolved: ext4: fix off-by-one error in do_split Syzkaller detected a use-after-free issue in ext4_insert_dentry that was caused by out-of-bounds access due to incorrect splitting in do_split. BUG: KASAN: use-after-free in ext4_insert_dentry+0x36a/0x6d0 fs/ext4/namei.c:2109 Write of size 251 at addr ffff888074572f14 by task syz-executor335/5847 CPU: 0 UID: 0 PID: 5847 Comm: syz-executor335 Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 ext4_insert_dentry+0x36a/0x6d0 fs/ext4/namei.c:2109 add_dirent_to_buf+0x3d9/0x750 fs/ext4/namei.c:2154 make_indexed_dir+0xf98/0x1600 fs/ext4/namei.c:2351 ext4_add_entry+0x222a/0x25d0 fs/ext4/namei.c:2455 ext4_add_nondir+0x8d/0x290 fs/ext4/namei.c:2796 ext4_symlink+0x920/0xb50 fs/ext4/namei.c:3431 vfs_symlink+0x137/0x2e0 fs/namei.c:4615 do_symlinkat+0x222/0x3a0 fs/namei.c:4641 __do_sys_symlink fs/namei.c:4662 [inline] __se_sys_symlink fs/namei.c:4660 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4660 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> The following loop is located right above 'if' statement. for (i = count-1; i >= 0; i--) { /* is more than half of this entry in 2nd half of the block? */ if (size + map[i].size/2 > blocksize/2) break; size += map[i].size; move++; } 'i' in this case could go down to -1, in which case sum of active entries wouldn't exceed half the block size, but previous behaviour would also do split in half if sum would exceed at the very last block, which in case of having too many long name files in a single block could lead to out-of-bounds access and following use-after-free. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. The Linux kernel CVE team has assigned CVE-2025-23150 to this issue. Affected and fixed versions =========================== Issue introduced in 5.9 with commit 5872331b3d91820e14716632ebb56b1399b34fe1 and fixed in 6.1.135 with commit 35d0aa6db9d93307085871ceab8a729594a98162 Issue introduced in 5.9 with commit 5872331b3d91820e14716632ebb56b1399b34fe1 and fixed in 6.6.88 with commit 2eeb1085bf7bd5c7ba796ca4119925fa5d336a3f Issue introduced in 5.9 with commit 5872331b3d91820e14716632ebb56b1399b34fe1 and fixed in 6.12.24 with commit 16d9067f00e3a7d1df7c3aa9c20d214923d27e10 Issue introduced in 5.9 with commit 5872331b3d91820e14716632ebb56b1399b34fe1 and fixed in 6.13.12 with commit 17df39f455f1289319d4d09e4826aa46852ffd17 Issue introduced in 5.9 with commit 5872331b3d91820e14716632ebb56b1399b34fe1 and fixed in 6.14.3 with commit ab0cc5c25552ae0d20eae94b40a93be11b080fc5 Issue introduced in 5.9 with commit 5872331b3d91820e14716632ebb56b1399b34fe1 and fixed in 6.15-rc2 with commit 94824ac9a8aaf2fb3c54b4bdde842db80ffa555d Issue introduced in 4.4.234 with commit 059b1480105478c5f68cf664301545b8cad6a7cf Issue introduced in 4.9.234 with commit 539ae3e03875dacaa9c388aff141ccbb4ef4ecb5 Issue introduced in 4.14.195 with commit fbbfd55a40d5d0806b59ee0403c75d5ac517533f Issue introduced in 4.19.142 with commit b3ddf6ba5e28a57729fff1605ae08e21be5c92e3 Issue introduced in 5.4.61 with commit ea54176e5821936d109bb45dc2c19bd53559e735 Issue introduced in 5.7.18 with commit e50fe43e3062e18846e99d9646b9c07b097eb1ed Issue introduced in 5.8.4 with commit 88e79f7a9841278fa8ff7ff6178bad12da002ffc Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2025-23150 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: fs/ext4/namei.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/35d0aa6db9d93307085871ceab8a729594a98162 https://git.kernel.org/stable/c/2eeb1085bf7bd5c7ba796ca4119925fa5d336a3f https://git.kernel.org/stable/c/16d9067f00e3a7d1df7c3aa9c20d214923d27e10 https://git.kernel.org/stable/c/17df39f455f1289319d4d09e4826aa46852ffd17 https://git.kernel.org/stable/c/ab0cc5c25552ae0d20eae94b40a93be11b080fc5 https://git.kernel.org/stable/c/94824ac9a8aaf2fb3c54b4bdde842db80ffa555d
Powered by blists - more mailing lists