This is a note to let you know that I've just added the patch titled x86/xen: Fix memory leak in xen_init_lock_cpu() to the 5.15-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_init_lock_cpu.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit becd886ace7ae072141c7a0bc4ca4a46991e60de Author: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx> Date: Wed Nov 23 23:58:58 2022 +0800 x86/xen: Fix memory leak in xen_init_lock_cpu() [ Upstream commit ca84ce153d887b1dc8b118029976cc9faf2a9b40 ] In xen_init_lock_cpu(), the @name has allocated new string by kasprintf(), if bind_ipi_to_irqhandler() fails, it should be freed, otherwise may lead to a memory leak issue, fix it. Fixes: 2d9e1e2f58b5 ("xen: implement Xen-specific spinlocks") Signed-off-by: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx> Reviewed-by: Juergen Gross <jgross@xxxxxxxx> Link: https://lore.kernel.org/r/20221123155858.11382-3-xiujianfeng@xxxxxxxxxx Signed-off-by: Juergen Gross <jgross@xxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index 043c73dfd2c9..5c6fc16e4b92 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -75,6 +75,7 @@ void xen_init_lock_cpu(int cpu) cpu, per_cpu(lock_kicker_irq, cpu)); name = kasprintf(GFP_KERNEL, "spinlock%d", cpu); + per_cpu(irq_name, cpu) = name; irq = bind_ipi_to_irqhandler(XEN_SPIN_UNLOCK_VECTOR, cpu, dummy_handler, @@ -85,7 +86,6 @@ void xen_init_lock_cpu(int cpu) if (irq >= 0) { disable_irq(irq); /* make sure it's never delivered */ per_cpu(lock_kicker_irq, cpu) = irq; - per_cpu(irq_name, cpu) = name; } printk("cpu %d spinlock event irq %d\n", cpu, irq); @@ -98,6 +98,8 @@ void xen_uninit_lock_cpu(int cpu) if (!xen_pvspin) return; + kfree(per_cpu(irq_name, cpu)); + per_cpu(irq_name, cpu) = NULL; /* * When booting the kernel with 'mitigations=auto,nosmt', the secondary * CPUs are not activated, and lock_kicker_irq is not initialized. @@ -108,8 +110,6 @@ void xen_uninit_lock_cpu(int cpu) unbind_from_irqhandler(irq, NULL); per_cpu(lock_kicker_irq, cpu) = -1; - kfree(per_cpu(irq_name, cpu)); - per_cpu(irq_name, cpu) = NULL; } PV_CALLEE_SAVE_REGS_THUNK(xen_vcpu_stolen);