| From bippy-1.2.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2025-37738: ext4: ignore xattrs past end |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ext4: ignore xattrs past end |
| |
| Once inside 'ext4_xattr_inode_dec_ref_all' we should |
| ignore xattrs entries past the 'end' entry. |
| |
| This fixes the following KASAN reported issue: |
| |
| ================================================================== |
| BUG: KASAN: slab-use-after-free in ext4_xattr_inode_dec_ref_all+0xb8c/0xe90 |
| Read of size 4 at addr ffff888012c120c4 by task repro/2065 |
| |
| CPU: 1 UID: 0 PID: 2065 Comm: repro Not tainted 6.13.0-rc2+ #11 |
| Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 |
| Call Trace: |
| <TASK> |
| dump_stack_lvl+0x1fd/0x300 |
| ? tcp_gro_dev_warn+0x260/0x260 |
| ? _printk+0xc0/0x100 |
| ? read_lock_is_recursive+0x10/0x10 |
| ? irq_work_queue+0x72/0xf0 |
| ? __virt_addr_valid+0x17b/0x4b0 |
| print_address_description+0x78/0x390 |
| print_report+0x107/0x1f0 |
| ? __virt_addr_valid+0x17b/0x4b0 |
| ? __virt_addr_valid+0x3ff/0x4b0 |
| ? __phys_addr+0xb5/0x160 |
| ? ext4_xattr_inode_dec_ref_all+0xb8c/0xe90 |
| kasan_report+0xcc/0x100 |
| ? ext4_xattr_inode_dec_ref_all+0xb8c/0xe90 |
| ext4_xattr_inode_dec_ref_all+0xb8c/0xe90 |
| ? ext4_xattr_delete_inode+0xd30/0xd30 |
| ? __ext4_journal_ensure_credits+0x5f0/0x5f0 |
| ? __ext4_journal_ensure_credits+0x2b/0x5f0 |
| ? inode_update_timestamps+0x410/0x410 |
| ext4_xattr_delete_inode+0xb64/0xd30 |
| ? ext4_truncate+0xb70/0xdc0 |
| ? ext4_expand_extra_isize_ea+0x1d20/0x1d20 |
| ? __ext4_mark_inode_dirty+0x670/0x670 |
| ? ext4_journal_check_start+0x16f/0x240 |
| ? ext4_inode_is_fast_symlink+0x2f2/0x3a0 |
| ext4_evict_inode+0xc8c/0xff0 |
| ? ext4_inode_is_fast_symlink+0x3a0/0x3a0 |
| ? do_raw_spin_unlock+0x53/0x8a0 |
| ? ext4_inode_is_fast_symlink+0x3a0/0x3a0 |
| evict+0x4ac/0x950 |
| ? proc_nr_inodes+0x310/0x310 |
| ? trace_ext4_drop_inode+0xa2/0x220 |
| ? _raw_spin_unlock+0x1a/0x30 |
| ? iput+0x4cb/0x7e0 |
| do_unlinkat+0x495/0x7c0 |
| ? try_break_deleg+0x120/0x120 |
| ? 0xffffffff81000000 |
| ? __check_object_size+0x15a/0x210 |
| ? strncpy_from_user+0x13e/0x250 |
| ? getname_flags+0x1dc/0x530 |
| __x64_sys_unlinkat+0xc8/0xf0 |
| do_syscall_64+0x65/0x110 |
| entry_SYSCALL_64_after_hwframe+0x67/0x6f |
| RIP: 0033:0x434ffd |
| Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 8 |
| RSP: 002b:00007ffc50fa7b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000107 |
| RAX: ffffffffffffffda RBX: 00007ffc50fa7e18 RCX: 0000000000434ffd |
| RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000005 |
| RBP: 00007ffc50fa7be0 R08: 0000000000000000 R09: 0000000000000000 |
| R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 |
| R13: 00007ffc50fa7e08 R14: 00000000004bbf30 R15: 0000000000000001 |
| </TASK> |
| |
| The buggy address belongs to the object at ffff888012c12000 |
| which belongs to the cache filp of size 360 |
| The buggy address is located 196 bytes inside of |
| freed 360-byte region [ffff888012c12000, ffff888012c12168) |
| |
| The buggy address belongs to the physical page: |
| page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12c12 |
| head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 |
| flags: 0x40(head|node=0|zone=0) |
| page_type: f5(slab) |
| raw: 0000000000000040 ffff888000ad7640 ffffea0000497a00 dead000000000004 |
| raw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 |
| head: 0000000000000040 ffff888000ad7640 ffffea0000497a00 dead000000000004 |
| head: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 |
| head: 0000000000000001 ffffea00004b0481 ffffffffffffffff 0000000000000000 |
| head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000 |
| page dumped because: kasan: bad access detected |
| |
| Memory state around the buggy address: |
| ffff888012c11f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |
| ffff888012c12000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| > ffff888012c12080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| ^ |
| ffff888012c12100: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc |
| ffff888012c12180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc |
| ================================================================== |
| |
| The Linux kernel CVE team has assigned CVE-2025-37738 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 5.4.293 with commit 6aff941cb0f7d0c897c3698ad2e30672709135e3 |
| Fixed in 5.10.237 with commit 76c365fa7e2a8bb85f0190cdb4b8cdc99b2fdce3 |
| Fixed in 5.15.181 with commit f737418b6de31c962c7192777ee4018906975383 |
| Fixed in 6.1.135 with commit cf9291a3449b04688b81e32621e88de8f4314b54 |
| Fixed in 6.6.88 with commit 362a90cecd36e8a5c415966d0b75b04a0270e4dd |
| Fixed in 6.12.24 with commit eb59cc31b6ea076021d14b04e7faab1636b87d0e |
| Fixed in 6.13.12 with commit 3bc6317033f365ce578eb6039445fb66162722fd |
| Fixed in 6.14.3 with commit 836e625b03a666cf93ff5be328c8cb30336db872 |
| Fixed in 6.15 with commit c8e008b60492cf6fd31ef127aea6d02fd3d314cd |
| |
| 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-2025-37738 |
| 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/xattr.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/6aff941cb0f7d0c897c3698ad2e30672709135e3 |
| https://git.kernel.org/stable/c/76c365fa7e2a8bb85f0190cdb4b8cdc99b2fdce3 |
| https://git.kernel.org/stable/c/f737418b6de31c962c7192777ee4018906975383 |
| https://git.kernel.org/stable/c/cf9291a3449b04688b81e32621e88de8f4314b54 |
| https://git.kernel.org/stable/c/362a90cecd36e8a5c415966d0b75b04a0270e4dd |
| https://git.kernel.org/stable/c/eb59cc31b6ea076021d14b04e7faab1636b87d0e |
| https://git.kernel.org/stable/c/3bc6317033f365ce578eb6039445fb66162722fd |
| https://git.kernel.org/stable/c/836e625b03a666cf93ff5be328c8cb30336db872 |
| https://git.kernel.org/stable/c/c8e008b60492cf6fd31ef127aea6d02fd3d314cd |
