| 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-2024-36013: Bluetooth: L2CAP: Fix slab-use-after-free in l2cap_connect() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| Bluetooth: L2CAP: Fix slab-use-after-free in l2cap_connect() |
| |
| Extend a critical section to prevent chan from early freeing. |
| Also make the l2cap_connect() return type void. Nothing is using the |
| returned value but it is ugly to return a potentially freed pointer. |
| Making it void will help with backports because earlier kernels did use |
| the return value. Now the compile will break for kernels where this |
| patch is not a complete fix. |
| |
| Call stack summary: |
| |
| [use] |
| l2cap_bredr_sig_cmd |
| l2cap_connect |
| ┌ mutex_lock(&conn->chan_lock); |
| │ chan = pchan->ops->new_connection(pchan); <- alloc chan |
| │ __l2cap_chan_add(conn, chan); |
| │ l2cap_chan_hold(chan); |
| │ list_add(&chan->list, &conn->chan_l); ... (1) |
| └ mutex_unlock(&conn->chan_lock); |
| chan->conf_state ... (4) <- use after free |
| |
| [free] |
| l2cap_conn_del |
| ┌ mutex_lock(&conn->chan_lock); |
| │ foreach chan in conn->chan_l: ... (2) |
| │ l2cap_chan_put(chan); |
| │ l2cap_chan_destroy |
| │ kfree(chan) ... (3) <- chan freed |
| └ mutex_unlock(&conn->chan_lock); |
| |
| ================================================================== |
| BUG: KASAN: slab-use-after-free in instrument_atomic_read |
| include/linux/instrumented.h:68 [inline] |
| BUG: KASAN: slab-use-after-free in _test_bit |
| include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] |
| BUG: KASAN: slab-use-after-free in l2cap_connect+0xa67/0x11a0 |
| net/bluetooth/l2cap_core.c:4260 |
| Read of size 8 at addr ffff88810bf040a0 by task kworker/u3:1/311 |
| |
| The Linux kernel CVE team has assigned CVE-2024-36013 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 3.0 with commit 73ffa904b78287f6acf8797e040150aa26a4af4a and fixed in 6.6.32 with commit cfe560c7050bfb37b0d2491bbe7cd8b59e77fdc5 |
| Issue introduced in 3.0 with commit 73ffa904b78287f6acf8797e040150aa26a4af4a and fixed in 6.8.11 with commit 826af9d2f69567c646ff46d10393d47e30ad23c6 |
| Issue introduced in 3.0 with commit 73ffa904b78287f6acf8797e040150aa26a4af4a and fixed in 6.9 with commit 4d7b41c0e43995b0e992b9f8903109275744b658 |
| |
| 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-2024-36013 |
| 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: |
| net/bluetooth/l2cap_core.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/cfe560c7050bfb37b0d2491bbe7cd8b59e77fdc5 |
| https://git.kernel.org/stable/c/826af9d2f69567c646ff46d10393d47e30ad23c6 |
| https://git.kernel.org/stable/c/4d7b41c0e43995b0e992b9f8903109275744b658 |
