SUSE: CVE-2023-52564: SUSE Linux Security Advisory
Description
In the Linux kernel, the following vulnerability has been resolved: Revert "tty: n_gsm: fix UAF in gsm_cleanup_mux" This reverts commit 9b9c8195f3f0d74a826077fc1c01b9ee74907239. The commit above is reverted as it did not solve the original issue. gsm_cleanup_mux() tries to free up the virtual ttys by calling gsm_dlci_release() for each available DLCI. There, dlci_put() is called to decrease the reference counter for the DLCI via tty_port_put() which finally calls gsm_dlci_free(). This already clears the pointer which is being checked in gsm_cleanup_mux() before calling gsm_dlci_release(). Therefore, it is not necessary to clear this pointer in gsm_cleanup_mux() as done in the reverted commit. The commit introduces a null pointer dereference: <TASK> ? __die+0x1f/0x70 ? page_fault_oops+0x156/0x420 ? search_exception_tables+0x37/0x50 ? fixup_exception+0x21/0x310 ? exc_page_fault+0x69/0x150 ? asm_exc_page_fault+0x26/0x30 ? tty_port_put+0x19/0xa0 gsmtty_cleanup+0x29/0x80 [n_gsm] release_one_tty+0x37/0xe0 process_one_work+0x1e6/0x3e0 worker_thread+0x4c/0x3d0 ? __pfx_worker_thread+0x10/0x10 kthread+0xe1/0x110 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2f/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> The actual issue is that nothing guards dlci_put() from being called multiple times while the tty driver was triggered but did not yet finished calling gsm_dlci_free().
Solution(s)
- suse-upgrade-cluster-md-kmp-64kb
- suse-upgrade-cluster-md-kmp-default
- suse-upgrade-cluster-md-kmp-rt
- suse-upgrade-dlm-kmp-64kb
- suse-upgrade-dlm-kmp-default
- suse-upgrade-dlm-kmp-rt
- suse-upgrade-dtb-allwinner
- suse-upgrade-dtb-altera
- suse-upgrade-dtb-amazon
- suse-upgrade-dtb-amd
- suse-upgrade-dtb-amlogic
- suse-upgrade-dtb-apm
- suse-upgrade-dtb-apple
- suse-upgrade-dtb-arm
- suse-upgrade-dtb-broadcom
- suse-upgrade-dtb-cavium
- suse-upgrade-dtb-exynos
- suse-upgrade-dtb-freescale
- suse-upgrade-dtb-hisilicon
- suse-upgrade-dtb-lg
- suse-upgrade-dtb-marvell
- suse-upgrade-dtb-mediatek
- suse-upgrade-dtb-nvidia
- suse-upgrade-dtb-qcom
- suse-upgrade-dtb-renesas
- suse-upgrade-dtb-rockchip
- suse-upgrade-dtb-socionext
- suse-upgrade-dtb-sprd
- suse-upgrade-dtb-xilinx
- suse-upgrade-gfs2-kmp-64kb
- suse-upgrade-gfs2-kmp-default
- suse-upgrade-gfs2-kmp-rt
- suse-upgrade-kernel-64kb
- suse-upgrade-kernel-64kb-devel
- suse-upgrade-kernel-64kb-extra
- suse-upgrade-kernel-64kb-livepatch-devel
- suse-upgrade-kernel-64kb-optional
- suse-upgrade-kernel-debug
- suse-upgrade-kernel-debug-devel
- suse-upgrade-kernel-debug-livepatch-devel
- suse-upgrade-kernel-debug-vdso
- suse-upgrade-kernel-default
- suse-upgrade-kernel-default-base
- suse-upgrade-kernel-default-base-rebuild
- suse-upgrade-kernel-default-devel
- suse-upgrade-kernel-default-extra
- suse-upgrade-kernel-default-livepatch
- suse-upgrade-kernel-default-livepatch-devel
- suse-upgrade-kernel-default-optional
- suse-upgrade-kernel-default-vdso
- suse-upgrade-kernel-devel
- suse-upgrade-kernel-devel-rt
- suse-upgrade-kernel-docs
- suse-upgrade-kernel-docs-html
- suse-upgrade-kernel-kvmsmall
- suse-upgrade-kernel-kvmsmall-devel
- suse-upgrade-kernel-kvmsmall-livepatch-devel
- suse-upgrade-kernel-kvmsmall-vdso
- suse-upgrade-kernel-macros
- suse-upgrade-kernel-obs-build
- suse-upgrade-kernel-obs-qa
- suse-upgrade-kernel-rt
- suse-upgrade-kernel-rt-devel
- suse-upgrade-kernel-rt-extra
- suse-upgrade-kernel-rt-livepatch
- suse-upgrade-kernel-rt-livepatch-devel
- suse-upgrade-kernel-rt-optional
- suse-upgrade-kernel-rt-vdso
- suse-upgrade-kernel-rt_debug
- suse-upgrade-kernel-rt_debug-devel
- suse-upgrade-kernel-rt_debug-livepatch-devel
- suse-upgrade-kernel-rt_debug-vdso
- suse-upgrade-kernel-source
- suse-upgrade-kernel-source-rt
- suse-upgrade-kernel-source-vanilla
- suse-upgrade-kernel-syms
- suse-upgrade-kernel-syms-rt
- suse-upgrade-kernel-zfcpdump
- suse-upgrade-kselftests-kmp-64kb
- suse-upgrade-kselftests-kmp-default
- suse-upgrade-kselftests-kmp-rt
- suse-upgrade-ocfs2-kmp-64kb
- suse-upgrade-ocfs2-kmp-default
- suse-upgrade-ocfs2-kmp-rt
- suse-upgrade-reiserfs-kmp-64kb
- suse-upgrade-reiserfs-kmp-default
- suse-upgrade-reiserfs-kmp-rt
- Lightweight Endpoint Agent
- Live Dashboards
- Real Risk Prioritization
- IT-Integrated Remediation Projects
- Cloud, Virtual, and Container Assessment
- Integrated Threat Feeds
- Easy-to-Use RESTful API
- Automation-Assisted Patching
- Automated Containment
With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.
– Scott Cheney, Manager of Information Security, Sierra View Medical Center