CVE - CVE-2024-41070

CVE-ID
CVE-2024-41070	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
In the Linux kernel, the following vulnerability has been resolved: KVM: PPC: Book3S HV: Prevent UAF in kvm_spapr_tce_attach_iommu_group() Al reported a possible use-after-free (UAF) in kvm_spapr_tce_attach_iommu_group(). It looks up `stt` from tablefd, but then continues to use it after doing fdput() on the returned fd. After the fdput() the tablefd is free to be closed by another thread. The close calls kvm_spapr_tce_release() and then release_spapr_tce_table() (via call_rcu()) which frees `stt`. Although there are calls to rcu_read_lock() in kvm_spapr_tce_attach_iommu_group() they are not sufficient to prevent the UAF, because `stt` is used outside the locked regions. With an artifcial delay after the fdput() and a userspace program which triggers the race, KASAN detects the UAF: BUG: KASAN: slab-use-after-free in kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm] Read of size 4 at addr c000200027552c30 by task kvm-vfio/2505 CPU: 54 PID: 2505 Comm: kvm-vfio Not tainted 6.10.0-rc3-next-20240612-dirty #1 Hardware name: 8335-GTH POWER9 0x4e1202 opal:skiboot-v6.5.3-35-g1851b2a06 PowerNV Call Trace: dump_stack_lvl+0xb4/0x108 (unreliable) print_report+0x2b4/0x6ec kasan_report+0x118/0x2b0 __asan_load4+0xb8/0xd0 kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm] kvm_vfio_set_attr+0x524/0xac0 [kvm] kvm_device_ioctl+0x144/0x240 [kvm] sys_ioctl+0x62c/0x1810 system_call_exception+0x190/0x440 system_call_vectored_common+0x15c/0x2ec ... Freed by task 0: ... kfree+0xec/0x3e0 release_spapr_tce_table+0xd4/0x11c [kvm] rcu_core+0x568/0x16a0 handle_softirqs+0x23c/0x920 do_softirq_own_stack+0x6c/0x90 do_softirq_own_stack+0x58/0x90 __irq_exit_rcu+0x218/0x2d0 irq_exit+0x30/0x80 arch_local_irq_restore+0x128/0x230 arch_local_irq_enable+0x1c/0x30 cpuidle_enter_state+0x134/0x5cc cpuidle_enter+0x6c/0xb0 call_cpuidle+0x7c/0x100 do_idle+0x394/0x410 cpu_startup_entry+0x60/0x70 start_secondary+0x3fc/0x410 start_secondary_prolog+0x10/0x14 Fix it by delaying the fdput() until `stt` is no longer in use, which is effectively the entire function. To keep the patch minimal add a call to fdput() at each of the existing return paths. Future work can convert the function to goto or __cleanup style cleanup. With the fix in place the test case no longer triggers the UAF.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
MISC:https://git.kernel.org/stable/c/4cdf6926f443c84f680213c7aafbe6f91a5fcbc0 URL:https://git.kernel.org/stable/c/4cdf6926f443c84f680213c7aafbe6f91a5fcbc0 MISC:https://git.kernel.org/stable/c/5f856023971f97fff74cfaf21b48ec320147b50a URL:https://git.kernel.org/stable/c/5f856023971f97fff74cfaf21b48ec320147b50a MISC:https://git.kernel.org/stable/c/82c7a4cf14aa866f8f7f09e662b02eddc49ee0bf URL:https://git.kernel.org/stable/c/82c7a4cf14aa866f8f7f09e662b02eddc49ee0bf MISC:https://git.kernel.org/stable/c/9975f93c760a32453d7639cf6fcf3f73b4e71ffe URL:https://git.kernel.org/stable/c/9975f93c760a32453d7639cf6fcf3f73b4e71ffe MISC:https://git.kernel.org/stable/c/a986fa57fd81a1430e00b3c6cf8a325d6f894a63 URL:https://git.kernel.org/stable/c/a986fa57fd81a1430e00b3c6cf8a325d6f894a63 MISC:https://git.kernel.org/stable/c/b26c8c85463ef27a522d24fcd05651f0bb039e47 URL:https://git.kernel.org/stable/c/b26c8c85463ef27a522d24fcd05651f0bb039e47 MISC:https://git.kernel.org/stable/c/be847bb20c809de8ac124431b556f244400b0491 URL:https://git.kernel.org/stable/c/be847bb20c809de8ac124431b556f244400b0491
Assigning CNA
kernel.org
Date Record Created
20240712	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20240712)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
This is an record on the CVE List, which provides common identifiers for publicly known cybersecurity vulnerabilities.
Search CVE Using Keywords: You can also search by reference using the CVE Reference Maps.
For More Information: CVE Request Web Form (select "Other" from dropdown)