| 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-2024-27399: Bluetooth: l2cap: fix null-ptr-deref in l2cap_chan_timeout |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| Bluetooth: l2cap: fix null-ptr-deref in l2cap_chan_timeout |
| |
| There is a race condition between l2cap_chan_timeout() and |
| l2cap_chan_del(). When we use l2cap_chan_del() to delete the |
| channel, the chan->conn will be set to null. But the conn could |
| be dereferenced again in the mutex_lock() of l2cap_chan_timeout(). |
| As a result the null pointer dereference bug will happen. The |
| KASAN report triggered by POC is shown below: |
| |
| [ 472.074580] ================================================================== |
| [ 472.075284] BUG: KASAN: null-ptr-deref in mutex_lock+0x68/0xc0 |
| [ 472.075308] Write of size 8 at addr 0000000000000158 by task kworker/0:0/7 |
| [ 472.075308] |
| [ 472.075308] CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.9.0-rc5-00356-g78c0094a146b #36 |
| [ 472.075308] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4 |
| [ 472.075308] Workqueue: events l2cap_chan_timeout |
| [ 472.075308] Call Trace: |
| [ 472.075308] <TASK> |
| [ 472.075308] dump_stack_lvl+0x137/0x1a0 |
| [ 472.075308] print_report+0x101/0x250 |
| [ 472.075308] ? __virt_addr_valid+0x77/0x160 |
| [ 472.075308] ? mutex_lock+0x68/0xc0 |
| [ 472.075308] kasan_report+0x139/0x170 |
| [ 472.075308] ? mutex_lock+0x68/0xc0 |
| [ 472.075308] kasan_check_range+0x2c3/0x2e0 |
| [ 472.075308] mutex_lock+0x68/0xc0 |
| [ 472.075308] l2cap_chan_timeout+0x181/0x300 |
| [ 472.075308] process_one_work+0x5d2/0xe00 |
| [ 472.075308] worker_thread+0xe1d/0x1660 |
| [ 472.075308] ? pr_cont_work+0x5e0/0x5e0 |
| [ 472.075308] kthread+0x2b7/0x350 |
| [ 472.075308] ? pr_cont_work+0x5e0/0x5e0 |
| [ 472.075308] ? kthread_blkcg+0xd0/0xd0 |
| [ 472.075308] ret_from_fork+0x4d/0x80 |
| [ 472.075308] ? kthread_blkcg+0xd0/0xd0 |
| [ 472.075308] ret_from_fork_asm+0x11/0x20 |
| [ 472.075308] </TASK> |
| [ 472.075308] ================================================================== |
| [ 472.094860] Disabling lock debugging due to kernel taint |
| [ 472.096136] BUG: kernel NULL pointer dereference, address: 0000000000000158 |
| [ 472.096136] #PF: supervisor write access in kernel mode |
| [ 472.096136] #PF: error_code(0x0002) - not-present page |
| [ 472.096136] PGD 0 P4D 0 |
| [ 472.096136] Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI |
| [ 472.096136] CPU: 0 PID: 7 Comm: kworker/0:0 Tainted: G B 6.9.0-rc5-00356-g78c0094a146b #36 |
| [ 472.096136] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4 |
| [ 472.096136] Workqueue: events l2cap_chan_timeout |
| [ 472.096136] RIP: 0010:mutex_lock+0x88/0xc0 |
| [ 472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88 |
| [ 472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246 |
| [ 472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865 |
| [ 472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78 |
| [ 472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f |
| [ 472.096136] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000 |
| [ 472.096136] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00 |
| [ 472.096136] FS: 0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000 |
| [ 472.096136] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| [ 472.096136] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0 |
| [ 472.096136] Call Trace: |
| [ 472.096136] <TASK> |
| [ 472.096136] ? __die_body+0x8d/0xe0 |
| [ 472.096136] ? page_fault_oops+0x6b8/0x9a0 |
| [ 472.096136] ? kernelmode_fixup_or_oops+0x20c/0x2a0 |
| [ 472.096136] ? do_user_addr_fault+0x1027/0x1340 |
| [ 472.096136] ? _printk+0x7a/0xa0 |
| [ 472.096136] ? mutex_lock+0x68/0xc0 |
| [ 472.096136] ? add_taint+0x42/0xd0 |
| [ 472.096136] ? exc_page_fault+0x6a/0x1b0 |
| [ 472.096136] ? asm_exc_page_fault+0x26/0x30 |
| [ 472.096136] ? mutex_lock+0x75/0xc0 |
| [ 472.096136] ? mutex_lock+0x88/0xc0 |
| [ 472.096136] ? mutex_lock+0x75/0xc0 |
| [ 472.096136] l2cap_chan_timeout+0x181/0x300 |
| [ 472.096136] process_one_work+0x5d2/0xe00 |
| [ 472.096136] worker_thread+0xe1d/0x1660 |
| [ 472.096136] ? pr_cont_work+0x5e0/0x5e0 |
| [ 472.096136] kthread+0x2b7/0x350 |
| [ 472.096136] ? pr_cont_work+0x5e0/0x5e0 |
| [ 472.096136] ? kthread_blkcg+0xd0/0xd0 |
| [ 472.096136] ret_from_fork+0x4d/0x80 |
| [ 472.096136] ? kthread_blkcg+0xd0/0xd0 |
| [ 472.096136] ret_from_fork_asm+0x11/0x20 |
| [ 472.096136] </TASK> |
| [ 472.096136] Modules linked in: |
| [ 472.096136] CR2: 0000000000000158 |
| [ 472.096136] ---[ end trace 0000000000000000 ]--- |
| [ 472.096136] RIP: 0010:mutex_lock+0x88/0xc0 |
| [ 472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88 |
| [ 472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246 |
| [ 472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865 |
| [ 472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78 |
| [ 472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f |
| [ 472.132932] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000 |
| [ 472.132932] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00 |
| [ 472.132932] FS: 0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000 |
| [ 472.132932] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| [ 472.132932] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0 |
| [ 472.132932] Kernel panic - not syncing: Fatal exception |
| [ 472.132932] Kernel Offset: disabled |
| [ 472.132932] ---[ end Kernel panic - not syncing: Fatal exception ]--- |
| |
| Add a check to judge whether the conn is null in l2cap_chan_timeout() |
| in order to mitigate the bug. |
| |
| The Linux kernel CVE team has assigned CVE-2024-27399 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 3.4 with commit 3df91ea20e744344100b10ae69a17211fcf5b207 and fixed in 4.19.314 with commit e137e2ba96e51902dc2878131823a96bf8e638ae |
| Issue introduced in 3.4 with commit 3df91ea20e744344100b10ae69a17211fcf5b207 and fixed in 5.4.276 with commit 6466ee65e5b27161c846c73ef407f49dfa1bd1d9 |
| Issue introduced in 3.4 with commit 3df91ea20e744344100b10ae69a17211fcf5b207 and fixed in 5.10.217 with commit 06acb75e7ed600d0bbf7bff5628aa8f24a97978c |
| Issue introduced in 3.4 with commit 3df91ea20e744344100b10ae69a17211fcf5b207 and fixed in 5.15.159 with commit e97e16433eb4533083b096a3824b93a5ca3aee79 |
| Issue introduced in 3.4 with commit 3df91ea20e744344100b10ae69a17211fcf5b207 and fixed in 6.1.91 with commit 8960ff650aec70485b40771cd8e6e8c4cb467d33 |
| Issue introduced in 3.4 with commit 3df91ea20e744344100b10ae69a17211fcf5b207 and fixed in 6.6.31 with commit 955b5b6c54d95b5e7444dfc81c95c8e013f27ac0 |
| Issue introduced in 3.4 with commit 3df91ea20e744344100b10ae69a17211fcf5b207 and fixed in 6.8.10 with commit eb86f955488c39526534211f2610e48a5cf8ead4 |
| Issue introduced in 3.4 with commit 3df91ea20e744344100b10ae69a17211fcf5b207 and fixed in 6.9 with commit adf0398cee86643b8eacde95f17d073d022f782c |
| |
| 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-2024-27399 |
| 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/e137e2ba96e51902dc2878131823a96bf8e638ae |
| https://git.kernel.org/stable/c/6466ee65e5b27161c846c73ef407f49dfa1bd1d9 |
| https://git.kernel.org/stable/c/06acb75e7ed600d0bbf7bff5628aa8f24a97978c |
| https://git.kernel.org/stable/c/e97e16433eb4533083b096a3824b93a5ca3aee79 |
| https://git.kernel.org/stable/c/8960ff650aec70485b40771cd8e6e8c4cb467d33 |
| https://git.kernel.org/stable/c/955b5b6c54d95b5e7444dfc81c95c8e013f27ac0 |
| https://git.kernel.org/stable/c/eb86f955488c39526534211f2610e48a5cf8ead4 |
| https://git.kernel.org/stable/c/adf0398cee86643b8eacde95f17d073d022f782c |
