[PATCH 6.1 0170/1146] x86/xen: Fix memory leak in xen_smp_intr_init{_pv}()

Greg Kroah-Hartman
2022-12-28T15:20:12Z

From: Xiu Jianfeng <xiujianfeng@huawei.com>

[ 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@huawei.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20221123155858.11382-2-xiujianfeng@huawei.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/xen/smp.c | 24 ++++++++++++------------
arch/x86/xen/smp_pv.c | 12 ++++++------
2 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index c3e1f9a7d43a..4b0d6fff88de 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 480be82e9b7b..6175f2c5c822 100644
--- a/arch/x86/xen/smp_pv.c
+++ b/arch/x86/xen/smp_pv.c
@@ -97,18 +97,18 @@ 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;
}
}

@@ -118,6 +118,7 @@ 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,
@@ -127,10 +128,10 @@ 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,
@@ -138,7 +139,6 @@ 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;
--
2.35.1