This is a note to let you know that I've just added the patch titled x86/xen: Fix memory leak in xen_smp_intr_init{_pv}() to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-xen-fix-memory-leak-in-xen_smp_intr_init-_pv.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e1f74d966885535cd414b9c238d7a8cebd68a9e4 Author: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx> Date: Wed Nov 23 23:58:57 2022 +0800 x86/xen: Fix memory leak in xen_smp_intr_init{_pv}() [ Upstream commit 69143f60868b3939ddc89289b29db593b647295e ] These local variables @{resched|pmu|callfunc...}_name saves the new string allocated by kasprintf(), and when bind_{v}ipi_to_irqhandler() fails, it goes to the @fail tag, and calls xen_smp_intr_free{_pv}() to free resource, however the new string is not saved, which cause a memory leak issue. fix it. Fixes: 9702785a747a ("i386: move xen") Signed-off-by: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx> Reviewed-by: Juergen Gross <jgross@xxxxxxxx> Link: https://lore.kernel.org/r/20221123155858.11382-2-xiujianfeng@xxxxxxxxxx Signed-off-by: Juergen Gross <jgross@xxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 63a3605b2225..a1cc855c539c 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -32,30 +32,30 @@ static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id) void xen_smp_intr_free(unsigned int cpu) { + kfree(per_cpu(xen_resched_irq, cpu).name); + per_cpu(xen_resched_irq, cpu).name = NULL; if (per_cpu(xen_resched_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL); per_cpu(xen_resched_irq, cpu).irq = -1; - kfree(per_cpu(xen_resched_irq, cpu).name); - per_cpu(xen_resched_irq, cpu).name = NULL; } + kfree(per_cpu(xen_callfunc_irq, cpu).name); + per_cpu(xen_callfunc_irq, cpu).name = NULL; if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL); per_cpu(xen_callfunc_irq, cpu).irq = -1; - kfree(per_cpu(xen_callfunc_irq, cpu).name); - per_cpu(xen_callfunc_irq, cpu).name = NULL; } + kfree(per_cpu(xen_debug_irq, cpu).name); + per_cpu(xen_debug_irq, cpu).name = NULL; if (per_cpu(xen_debug_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL); per_cpu(xen_debug_irq, cpu).irq = -1; - kfree(per_cpu(xen_debug_irq, cpu).name); - per_cpu(xen_debug_irq, cpu).name = NULL; } + kfree(per_cpu(xen_callfuncsingle_irq, cpu).name); + per_cpu(xen_callfuncsingle_irq, cpu).name = NULL; if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq, NULL); per_cpu(xen_callfuncsingle_irq, cpu).irq = -1; - kfree(per_cpu(xen_callfuncsingle_irq, cpu).name); - per_cpu(xen_callfuncsingle_irq, cpu).name = NULL; } } @@ -65,6 +65,7 @@ int xen_smp_intr_init(unsigned int cpu) char *resched_name, *callfunc_name, *debug_name; resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu); + per_cpu(xen_resched_irq, cpu).name = resched_name; rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR, cpu, xen_reschedule_interrupt, @@ -74,9 +75,9 @@ int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_resched_irq, cpu).irq = rc; - per_cpu(xen_resched_irq, cpu).name = resched_name; callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu); + per_cpu(xen_callfunc_irq, cpu).name = callfunc_name; rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR, cpu, xen_call_function_interrupt, @@ -86,10 +87,10 @@ int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_callfunc_irq, cpu).irq = rc; - per_cpu(xen_callfunc_irq, cpu).name = callfunc_name; if (!xen_fifo_events) { debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu); + per_cpu(xen_debug_irq, cpu).name = debug_name; rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt, IRQF_PERCPU | IRQF_NOBALANCING, @@ -97,10 +98,10 @@ int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_debug_irq, cpu).irq = rc; - per_cpu(xen_debug_irq, cpu).name = debug_name; } callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu); + per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name; rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR, cpu, xen_call_function_single_interrupt, @@ -110,7 +111,6 @@ int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_callfuncsingle_irq, cpu).irq = rc; - per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name; return 0; diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c index 9d9777ded5f7..928fbe63c96f 100644 --- a/arch/x86/xen/smp_pv.c +++ b/arch/x86/xen/smp_pv.c @@ -98,18 +98,18 @@ asmlinkage __visible void cpu_bringup_and_idle(void) void xen_smp_intr_free_pv(unsigned int cpu) { + kfree(per_cpu(xen_irq_work, cpu).name); + per_cpu(xen_irq_work, cpu).name = NULL; if (per_cpu(xen_irq_work, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_irq_work, cpu).irq, NULL); per_cpu(xen_irq_work, cpu).irq = -1; - kfree(per_cpu(xen_irq_work, cpu).name); - per_cpu(xen_irq_work, cpu).name = NULL; } + kfree(per_cpu(xen_pmu_irq, cpu).name); + per_cpu(xen_pmu_irq, cpu).name = NULL; if (per_cpu(xen_pmu_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_pmu_irq, cpu).irq, NULL); per_cpu(xen_pmu_irq, cpu).irq = -1; - kfree(per_cpu(xen_pmu_irq, cpu).name); - per_cpu(xen_pmu_irq, cpu).name = NULL; } } @@ -119,6 +119,7 @@ int xen_smp_intr_init_pv(unsigned int cpu) char *callfunc_name, *pmu_name; callfunc_name = kasprintf(GFP_KERNEL, "irqwork%d", cpu); + per_cpu(xen_irq_work, cpu).name = callfunc_name; rc = bind_ipi_to_irqhandler(XEN_IRQ_WORK_VECTOR, cpu, xen_irq_work_interrupt, @@ -128,10 +129,10 @@ int xen_smp_intr_init_pv(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_irq_work, cpu).irq = rc; - per_cpu(xen_irq_work, cpu).name = callfunc_name; if (is_xen_pmu) { pmu_name = kasprintf(GFP_KERNEL, "pmu%d", cpu); + per_cpu(xen_pmu_irq, cpu).name = pmu_name; rc = bind_virq_to_irqhandler(VIRQ_XENPMU, cpu, xen_pmu_irq_handler, IRQF_PERCPU|IRQF_NOBALANCING, @@ -139,7 +140,6 @@ int xen_smp_intr_init_pv(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_pmu_irq, cpu).irq = rc; - per_cpu(xen_pmu_irq, cpu).name = pmu_name; } return 0;