发布于3月6日3月6日 Members SUSE: CVE-2023-52854: SUSE Linux Security Advisory Severity 4 CVSS (AV:L/AC:M/Au:N/C:P/I:P/A:P) Published 05/21/2024 Created 06/14/2024 Added 06/13/2024 Modified 02/06/2025 Description In the Linux kernel, the following vulnerability has been resolved: padata: Fix refcnt handling in padata_free_shell() In a high-load arm64 environment, the pcrypt_aead01 test in LTP can lead to system UAF (Use-After-Free) issues. Due to the lengthy analysis of the pcrypt_aead01 function call, I'll describe the problem scenario using a simplified model: Suppose there's a user of padata named `user_function` that adheres to the padata requirement of calling `padata_free_shell` after `serial()` has been invoked, as demonstrated in the following code: ```c struct request { struct padata_priv padata; struct completion *done; }; void parallel(struct padata_priv *padata) { do_something(); } void serial(struct padata_priv *padata) { struct request *request = container_of(padata, struct request, padata); complete(request->done); } void user_function() { DECLARE_COMPLETION(done) padata->parallel = parallel; padata->serial = serial; padata_do_parallel(); wait_for_completion(&done); padata_free_shell(); } ``` In the corresponding padata.c file, there's the following code: ```c static void padata_serial_worker(struct work_struct *serial_work) { ... cnt = 0; while (!list_empty(&local_list)) { ... padata->serial(padata); cnt++; } local_bh_enable(); if (refcount_sub_and_test(cnt, &pd->refcnt)) padata_free_pd(pd); } ``` Because of the high system load and the accumulation of unexecuted softirq at this moment, `local_bh_enable()` in padata takes longer to execute than usual. Subsequently, when accessing `pd->refcnt`, `pd` has already been released by `padata_free_shell()`, resulting in a UAF issue with `pd->refcnt`. The fix is straightforward: add `refcount_dec_and_test` before calling `padata_free_pd` in `padata_free_shell`. Solution(s) suse-upgrade-cluster-md-kmp-64kb suse-upgrade-cluster-md-kmp-azure suse-upgrade-cluster-md-kmp-default suse-upgrade-cluster-md-kmp-rt suse-upgrade-dlm-kmp-64kb suse-upgrade-dlm-kmp-azure 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-azure 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-azure suse-upgrade-kernel-azure-devel suse-upgrade-kernel-azure-extra suse-upgrade-kernel-azure-livepatch-devel suse-upgrade-kernel-azure-optional suse-upgrade-kernel-azure-vdso 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-azure 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-azure suse-upgrade-kernel-source-rt suse-upgrade-kernel-source-vanilla suse-upgrade-kernel-syms suse-upgrade-kernel-syms-azure suse-upgrade-kernel-syms-rt suse-upgrade-kernel-zfcpdump suse-upgrade-kselftests-kmp-64kb suse-upgrade-kselftests-kmp-azure suse-upgrade-kselftests-kmp-default suse-upgrade-kselftests-kmp-rt suse-upgrade-ocfs2-kmp-64kb suse-upgrade-ocfs2-kmp-azure suse-upgrade-ocfs2-kmp-default suse-upgrade-ocfs2-kmp-rt suse-upgrade-reiserfs-kmp-64kb suse-upgrade-reiserfs-kmp-azure suse-upgrade-reiserfs-kmp-default suse-upgrade-reiserfs-kmp-rt References https://attackerkb.com/topics/cve-2023-52854 CVE - 2023-52854
