high CVSS 7.8

CVE-2024-56541·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: fix use-after-free in ath12k_dp_cc_cleanup() During ath12k module removal, in ath12k_core_deinit(), ath12k_mac_destroy() un-registers ah->hw from mac80211 and frees the ah->hw as well as all the ar's in it. After this ath12k_core_soc_destroy()-> ath12k_dp_free()-> ath12k_dp_cc_cleanup() tries to access one of the freed ar's from pending skb. This is because during mac destroy, driver failed to flush few data packets, which were accessed later in ath12k_dp_cc_cleanup() and freed, but using ar from the packet led to this use-after-free. BUG: KASAN: use-after-free in ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] Write of size 4 at addr ffff888150bd3514 by task modprobe/8926 CPU: 0 UID: 0 PID: 8926 Comm: modprobe Not tainted 6.11.0-rc2-wt-ath+ #1746 Hardware name: Intel(R) Client Systems NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0067.2021.0528.1339 05/28/2021 Call Trace: <TASK> dump_stack_lvl+0x7d/0xe0 print_address_description.constprop.0+0x33/0x3a0 print_report+0xb5/0x260 ? kasan_addr_to_slab+0x24/0x80 kasan_report+0xd8/0x110 ? ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] ? ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] kasan_check_range+0xf3/0x1a0 __kasan_check_write+0x14/0x20 ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] ath12k_dp_free+0x178/0x420 [ath12k] ath12k_core_stop+0x176/0x200 [ath12k] ath12k_core_deinit+0x13f/0x210 [ath12k] ath12k_pci_remove+0xad/0x1c0 [ath12k] pci_device_remove+0x9b/0x1b0 device_remove+0xbf/0x150 device_release_driver_internal+0x3c3/0x580 ? __kasan_check_read+0x11/0x20 driver_detach+0xc4/0x190 bus_remove_driver+0x130/0x2a0 driver_unregister+0x68/0x90 pci_unregister_driver+0x24/0x240 ? find_module_all+0x13e/0x1e0 ath12k_pci_exit+0x10/0x20 [ath12k] __do_sys_delete_module+0x32c/0x580 ? module_flags+0x2f0/0x2f0 ? kmem_cache_free+0xf0/0x410 ? __fput+0x56f/0xab0 ? __fput+0x56f/0xab0 ? debug_smp_processor_id+0x17/0x20 __x64_sys_delete_module+0x4f/0x70 x64_sys_call+0x522/0x9f0 do_syscall_64+0x64/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f8182c6ac8b Commit 24de1b7b231c ("wifi: ath12k: fix flush failure in recovery scenarios") added the change to decrement the pending packets count in case of recovery which make sense as ah->hw as well all ar's in it are intact during recovery, but during core deinit there is no use in decrementing packets count or waking up the empty waitq as the module is going to be removed also ar's from pending skb's can't be used and the packets should just be released back. To fix this, avoid accessing ar from skb->cb when driver is being unregistered. Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.1.1-00214-QCAHKSWPL_SILICONZ-1 Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Severity
high
Software
Kernel
Fixed in
6.12.2
Published
2024-12-27

Affected versions

From: 6.12

Until: 6.12.2

Fixed in: 6.12.2

How to fix this CVE

Update your Linux kernel to version 6.12.2 or later to resolve a use-after-free vulnerability in the ath12k WiFi driver that occurs during module removal. The vulnerability causes the driver to reference freed memory when cleaning up pending network packets, potentially leading to kernel crashes or memory corruption. Apply this patch immediately if you are running affected kernel versions (6.12.0 to 6.12.1) on systems with Qualcomm WiFi hardware.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your kernel version with `uname -r` and verify if it falls within 6.12.0-6.12.1 range
  2. Step 2: Verify ath12k WiFi driver is loaded with `lsmod | grep ath12k`
  3. Step 3: Search kernel logs for use-after-free errors during module operations using `dmesg | grep -i 'use-after-free\|ath12k_dp_cc_cleanup\|KASAN'`
  4. Step 4: Confirm the patch is applied by checking kernel version is 6.12.2+ with `uname -r` and rebuild modules if needed with `sudo update-initramfs -u`

FAQ

What is CVE-2024-56541?

CVE-2024-56541 is a use-after-free memory vulnerability in the Linux kernel's ath12k WiFi driver where freed hardware resources are accessed during module cleanup, occurring when the driver fails to properly flush pending network packets before destroying radio interfaces.

Is CVE-2024-56541 being actively exploited?

No, there is no evidence of active exploitation in the wild. This is a kernel stability issue that requires local access and affects module removal operations rather than normal runtime functionality.

What versions of Kernel are affected by CVE-2024-56541?

Linux kernel versions 6.12.0 through 6.12.1 are affected. The vulnerability has been patched in kernel version 6.12.2 and later.

How do I check if my server is vulnerable to CVE-2024-56541?

Run `uname -r` to check your kernel version. If it shows 6.12.0 or 6.12.1 and `lsmod | grep ath12k` confirms the WiFi driver is loaded, your system is vulnerable.

Does Defensia detect CVE-2024-56541?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server, CVE-2024-56541 will appear in your dashboard with remediation steps.

Related Kernel CVEs

CVE-2024-42256CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: cifs: Fix server re-repick on subrequest retry When a subrequest is marked for needing retry, netfs will call cifs_prepare_write() which will make cifs repick the server for the op before renegotiating credits; it then calls cifs_issue_write() which invokes smb2_async_writev() - which re-repicks the server. If a different server is then selected, this causes the increment of server->in_flight to happen against one record and the decrement to happen against another, leading to misaccounting. Fix this by just removing the repick code in smb2_async_writev(). As this is only called from netfslib-driven code, cifs_prepare_write() should always have been called first, and so server should never be NULL and the preparatory step is repeated in the event that we do a retry. The problem manifests as a warning looking something like: WARNING: CPU: 4 PID: 72896 at fs/smb/client/smb2ops.c:97 smb2_add_credits+0x3f0/0x9e0 [cifs] ... RIP: 0010:smb2_add_credits+0x3f0/0x9e0 [cifs] ... smb2_writev_callback+0x334/0x560 [cifs] cifs_demultiplex_thread+0x77a/0x11b0 [cifs] kthread+0x187/0x1d0 ret_from_fork+0x34/0x60 ret_from_fork_asm+0x1a/0x30 Which may be triggered by a number of different xfstests running against an Azure server in multichannel mode. generic/249 seems the most repeatable, but generic/215, generic/249 and generic/308 may also show it.
CVE-2024-36031CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: keys: Fix overwrite of key expiration on instantiation The expiry time of a key is unconditionally overwritten during instantiation, defaulting to turn it permanent. This causes a problem for DNS resolution as the expiration set by user-space is overwritten to TIME64_MAX, disabling further DNS updates. Fix this by restoring the condition that key_set_expiry is only called when the pre-parser sets a specific expiry.
CVE-2024-38612CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: fix invalid unregister error path The error path of seg6_init() is wrong in case CONFIG_IPV6_SEG6_LWTUNNEL is not defined. In that case if seg6_hmac_init() fails, the genl_unregister_family() isn't called. This issue exist since commit 46738b1317e1 ("ipv6: sr: add option to control lwtunnel support"), and commit 5559cea2d5aa ("ipv6: sr: fix possible use-after-free and null-ptr-deref") replaced unregister_pernet_subsys() with genl_unregister_family() in this error path.
CVE-2024-38623CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Use variable length array instead of fixed size Should fix smatch warning: ntfs_set_label() error: __builtin_memcpy() 'uni->name' too small (20 vs 256)
CVE-2021-47548CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port() The if statement: if (port >= DSAF_GE_NUM) return; limits the value of port less than DSAF_GE_NUM (i.e., 8). However, if the value of port is 6 or 7, an array overflow could occur: port_rst_off = dsaf_dev->mac_cb[port]->port_rst_off; because the length of dsaf_dev->mac_cb is DSAF_MAX_PORT_NUM (i.e., 6). To fix this possible array overflow, we first check port and if it is greater than or equal to DSAF_MAX_PORT_NUM, the function returns.

References

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