| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-44939: jfs: fix null ptr deref in dtInsertEntry |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| jfs: fix null ptr deref in dtInsertEntry |
| |
| [syzbot reported] |
| general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI |
| KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] |
| CPU: 0 PID: 5061 Comm: syz-executor404 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 |
| Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 |
| RIP: 0010:dtInsertEntry+0xd0c/0x1780 fs/jfs/jfs_dtree.c:3713 |
| ... |
| [Analyze] |
| In dtInsertEntry(), when the pointer h has the same value as p, after writing |
| name in UniStrncpy_to_le(), p->header.flag will be cleared. This will cause the |
| previously true judgment "p->header.flag & BT-LEAF" to change to no after writing |
| the name operation, this leads to entering an incorrect branch and accessing the |
| uninitialized object ih when judging this condition for the second time. |
| |
| [Fix] |
| After got the page, check freelist first, if freelist == 0 then exit dtInsert() |
| and return -EINVAL. |
| |
| The Linux kernel CVE team has assigned CVE-2024-44939 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.1.107 with commit 53023ab11836ac56fd75f7a71ec1356e50920fa9 |
| Fixed in 6.6.47 with commit 6ea10dbb1e6c58384136e9adfd75f81951e423f6 |
| Fixed in 6.10.6 with commit 9c2ac38530d1a3ee558834dfa16c85a40fd0e702 |
| Fixed in 6.11 with commit ce6dede912f064a855acf6f04a04cbb2c25b8c8c |
| |
| 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-2024-44939 |
| 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_dtree.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/53023ab11836ac56fd75f7a71ec1356e50920fa9 |
| https://git.kernel.org/stable/c/6ea10dbb1e6c58384136e9adfd75f81951e423f6 |
| https://git.kernel.org/stable/c/9c2ac38530d1a3ee558834dfa16c85a40fd0e702 |
| https://git.kernel.org/stable/c/ce6dede912f064a855acf6f04a04cbb2c25b8c8c |
