CVE-2022-50700
10h55 +00:00
CVE 설명
wifi: ath10k: Delay the unmapping of the buffer
In the Linux kernel, the following vulnerability has been resolved: wifi: ath10k: Delay the unmapping of the buffer On WCN3990, we are seeing a rare scenario where copy engine hardware is sending a copy complete interrupt to the host driver while still processing the buffer that the driver has sent, this is leading into an SMMU fault triggering kernel panic. This is happening on copy engine channel 3 (CE3) where the driver normally enqueues WMI commands to the firmware. Upon receiving a copy complete interrupt, host driver will immediately unmap and frees the buffer presuming that hardware has processed the buffer. In the issue case, upon receiving copy complete interrupt, host driver will unmap and free the buffer but since hardware is still accessing the buffer (which in this case got unmapped in parallel), SMMU hardware will trigger an SMMU fault resulting in a kernel panic. In order to avoid this, as a work around, add a delay before unmapping the copy engine source DMA buffer. This is conditionally done for WCN3990 and only for the CE3 channel where issue is seen. Below is the crash signature: wifi smmu error: kernel: [ 10.120965] arm-smmu 15000000.iommu: Unhandled context fault: fsr=0x402, iova=0x7fdfd8ac0, fsynr=0x500003,cbfrsynra=0xc1, cb=6 arm-smmu 15000000.iommu: Unhandled context fault:fsr=0x402, iova=0x7fe06fdc0, fsynr=0x710003, cbfrsynra=0xc1, cb=6 qcom-q6v5-mss 4080000.remoteproc: fatal error received: err_qdi.c:1040:EF:wlan_process:0x1:WLAN RT:0x2091: cmnos_thread.c:3998:Asserted in copy_engine.c:AXI_ERROR_DETECTED:2149 remoteproc remoteproc0: crash detected in 4080000.remoteproc: type fatal error <3> remoteproc remoteproc0: handling crash #1 in 4080000.remoteproc pc : __arm_lpae_unmap+0x500/0x514 lr : __arm_lpae_unmap+0x4bc/0x514 sp : ffffffc011ffb530 x29: ffffffc011ffb590 x28: 0000000000000000 x27: 0000000000000000 x26: 0000000000000004 x25: 0000000000000003 x24: ffffffc011ffb890 x23: ffffffa762ef9be0 x22: ffffffa77244ef00 x21: 0000000000000009 x20: 00000007fff7c000 x19: 0000000000000003 x18: 0000000000000000 x17: 0000000000000004 x16: ffffffd7a357d9f0 x15: 0000000000000000 x14: 00fd5d4fa7ffffff x13: 000000000000000e x12: 0000000000000000 x11: 00000000ffffffff x10: 00000000fffffe00 x9 : 000000000000017c x8 : 000000000000000c x7 : 0000000000000000 x6 : ffffffa762ef9000 x5 : 0000000000000003 x4 : 0000000000000004 x3 : 0000000000001000 x2 : 00000007fff7c000 x1 : ffffffc011ffb890 x0 : 0000000000000000 Call trace: __arm_lpae_unmap+0x500/0x514 __arm_lpae_unmap+0x4bc/0x514 __arm_lpae_unmap+0x4bc/0x514 arm_lpae_unmap_pages+0x78/0xa4 arm_smmu_unmap_pages+0x78/0x104 __iommu_unmap+0xc8/0x1e4 iommu_unmap_fast+0x38/0x48 __iommu_dma_unmap+0x84/0x104 iommu_dma_free+0x34/0x50 dma_free_attrs+0xa4/0xd0 ath10k_htt_rx_free+0xc4/0xf4 [ath10k_core] ath10k_core_stop+0x64/0x7c [ath10k_core] ath10k_halt+0x11c/0x180 [ath10k_core] ath10k_stop+0x54/0x94 [ath10k_core] drv_stop+0x48/0x1c8 [mac80211] ieee80211_do_open+0x638/0x77c [mac80211] ieee80211_open+0x48/0x5c [mac80211] __dev_open+0xb4/0x174 __dev_change_flags+0xc4/0x1dc dev_change_flags+0x3c/0x7c devinet_ioctl+0x2b4/0x580 inet_ioctl+0xb0/0x1b4 sock_do_ioctl+0x4c/0x16c compat_ifreq_ioctl+0x1cc/0x35c compat_sock_ioctl+0x110/0x2ac __arm64_compat_sys_ioctl+0xf4/0x3e0 el0_svc_common+0xb4/0x17c el0_svc_compat_handler+0x2c/0x58 el0_svc_compat+0x8/0x2c Tested-on: WCN3990 hw1.0 SNOC WLAN.HL.2.0-01387-QCAHLSWMTPLZ-1CVE 정보
메트릭
| 메트릭 | 점수 | 심각도 | CVSS 벡터 | 출처 |
|---|---|---|---|---|
| V3.1 | 7.5 | HIGH |
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
추가 정보
Base: Exploitabilty MetricsThe Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component. Attack Vector This metric reflects the context by which vulnerability exploitation is possible. Adjacent The vulnerable component is bound to the network stack, but the attack is limited at the protocol level to a logically adjacent topology. This can mean an attack must be launched from the same shared physical (e.g., Bluetooth or IEEE 802.11) or logical (e.g., local IP subnet) network, or from within a secure or otherwise limited administrative domain (e.g., MPLS, secure VPN to an administrative network zone). Attack Complexity This metric describes the conditions beyond the attacker’s control that must exist in order to exploit the vulnerability. High successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. Privileges Required This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability. None The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack. User Interaction This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable component. None The vulnerable system can be exploited without interaction from any user. Base: Scope MetricsThe Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope. Scope Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs. Unchanged An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority. Base: Impact MetricsThe Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve. Confidentiality Impact This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability. High There is a total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server. Integrity Impact This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. High There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component. Availability Impact This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability. High There is a total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable). Temporal MetricsThe Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence in the description of a vulnerability. Environmental MetricsThese metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability. |
