| 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-2025-37742: jfs: Fix uninit-value access of imap allocated in the diMount() function |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| jfs: Fix uninit-value access of imap allocated in the diMount() function |
| |
| syzbot reports that hex_dump_to_buffer is using uninit-value: |
| |
| ===================================================== |
| BUG: KMSAN: uninit-value in hex_dump_to_buffer+0x888/0x1100 lib/hexdump.c:171 |
| hex_dump_to_buffer+0x888/0x1100 lib/hexdump.c:171 |
| print_hex_dump+0x13d/0x3e0 lib/hexdump.c:276 |
| diFree+0x5ba/0x4350 fs/jfs/jfs_imap.c:876 |
| jfs_evict_inode+0x510/0x550 fs/jfs/inode.c:156 |
| evict+0x723/0xd10 fs/inode.c:796 |
| iput_final fs/inode.c:1946 [inline] |
| iput+0x97b/0xdb0 fs/inode.c:1972 |
| txUpdateMap+0xf3e/0x1150 fs/jfs/jfs_txnmgr.c:2367 |
| txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline] |
| jfs_lazycommit+0x627/0x11d0 fs/jfs/jfs_txnmgr.c:2733 |
| kthread+0x6b9/0xef0 kernel/kthread.c:464 |
| ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:148 |
| ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 |
| |
| Uninit was created at: |
| slab_post_alloc_hook mm/slub.c:4121 [inline] |
| slab_alloc_node mm/slub.c:4164 [inline] |
| __kmalloc_cache_noprof+0x8e3/0xdf0 mm/slub.c:4320 |
| kmalloc_noprof include/linux/slab.h:901 [inline] |
| diMount+0x61/0x7f0 fs/jfs/jfs_imap.c:105 |
| jfs_mount+0xa8e/0x11d0 fs/jfs/jfs_mount.c:176 |
| jfs_fill_super+0xa47/0x17c0 fs/jfs/super.c:523 |
| get_tree_bdev_flags+0x6ec/0x910 fs/super.c:1636 |
| get_tree_bdev+0x37/0x50 fs/super.c:1659 |
| jfs_get_tree+0x34/0x40 fs/jfs/super.c:635 |
| vfs_get_tree+0xb1/0x5a0 fs/super.c:1814 |
| do_new_mount+0x71f/0x15e0 fs/namespace.c:3560 |
| path_mount+0x742/0x1f10 fs/namespace.c:3887 |
| do_mount fs/namespace.c:3900 [inline] |
| __do_sys_mount fs/namespace.c:4111 [inline] |
| __se_sys_mount+0x71f/0x800 fs/namespace.c:4088 |
| __x64_sys_mount+0xe4/0x150 fs/namespace.c:4088 |
| x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166 |
| do_syscall_x64 arch/x86/entry/common.c:52 [inline] |
| do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 |
| entry_SYSCALL_64_after_hwframe+0x77/0x7f |
| ===================================================== |
| |
| The reason is that imap is not properly initialized after memory |
| allocation. It will cause the snprintf() function to write uninitialized |
| data into linebuf within hex_dump_to_buffer(). |
| |
| Fix this by using kzalloc instead of kmalloc to clear its content at the |
| beginning in diMount(). |
| |
| The Linux kernel CVE team has assigned CVE-2025-37742 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 5.15.181 with commit 4f10732712fce33e53703ffe5ed9155f23814097 |
| Fixed in 6.1.135 with commit cab1852368dd74d629ee02abdbc559218ca64dde |
| Fixed in 6.6.88 with commit 067347e00a3a7d04afed93f080c6c131e5dd15ee |
| Fixed in 6.12.24 with commit 63148ce4904faa668daffdd1d3c1199ae315ef2c |
| Fixed in 6.13.12 with commit 7057f3aab47629d38e54eae83505813cf0da1e4b |
| Fixed in 6.14.3 with commit d0d7eca253ccd0619b3d2b683ffe32218ebca9ac |
| Fixed in 6.15 with commit 9629d7d66c621671d9a47afe27ca9336bfc8a9ea |
| |
| 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-2025-37742 |
| 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/jfs/jfs_imap.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/4f10732712fce33e53703ffe5ed9155f23814097 |
| https://git.kernel.org/stable/c/cab1852368dd74d629ee02abdbc559218ca64dde |
| https://git.kernel.org/stable/c/067347e00a3a7d04afed93f080c6c131e5dd15ee |
| https://git.kernel.org/stable/c/63148ce4904faa668daffdd1d3c1199ae315ef2c |
| https://git.kernel.org/stable/c/7057f3aab47629d38e54eae83505813cf0da1e4b |
| https://git.kernel.org/stable/c/d0d7eca253ccd0619b3d2b683ffe32218ebca9ac |
| https://git.kernel.org/stable/c/9629d7d66c621671d9a47afe27ca9336bfc8a9ea |
