From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chintan Pandya Subject: [PATCH v1 3/4] arm64: Fix the page leak in pud/pmd_set_huge Date: Wed, 14 Mar 2018 14:18:24 +0530 Message-ID: <1521017305-28518-4-git-send-email-cpandya@codeaurora.org> References: <1521017305-28518-1-git-send-email-cpandya@codeaurora.org> Return-path: In-Reply-To: <1521017305-28518-1-git-send-email-cpandya@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org To: catalin.marinas@arm.com, will.deacon@arm.com, arnd@arndb.de Cc: mark.rutland@arm.com, ard.biesheuvel@linaro.org, marc.zyngier@arm.com, james.morse@arm.com, kristina.martsenko@arm.com, takahiro.akashi@linaro.org, gregkh@linuxfoundation.org, tglx@linutronix.de, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, akpm@linux-foundation.org, toshi.kani@hpe.com, Chintan Pandya List-Id: linux-arch.vger.kernel.org While setting huge page, we need to take care of previously existing next level mapping. Since, we are going to overrite previous mapping, the only reference to next level page table will get lost and the next level page table will be zombie, occupying space forever. So, free it before overriding. Signed-off-by: Chintan Pandya --- arch/arm64/mm/mmu.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 8c704f1..c0df264 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -32,7 +32,7 @@ #include #include #include - +#include #include #include #include @@ -45,6 +45,7 @@ #include #include #include +#include #define NO_BLOCK_MAPPINGS BIT(0) #define NO_CONT_MAPPINGS BIT(1) @@ -939,6 +940,9 @@ int pud_set_huge(pud_t *pudp, phys_addr_t phys, pgprot_t prot) return 0; BUG_ON(phys & ~PUD_MASK); + if (pud_val(*pud) && !pud_huge(*pud)) + free_page((unsigned long)__va(pud_val(*pud))); + set_pud(pudp, pfn_pud(__phys_to_pfn(phys), sect_prot)); return 1; } @@ -953,6 +957,9 @@ int pmd_set_huge(pmd_t *pmdp, phys_addr_t phys, pgprot_t prot) return 0; BUG_ON(phys & ~PMD_MASK); + if (pmd_val(*pmd) && !pmd_huge(*pmd)) + free_page((unsigned long)__va(pmd_val(*pmd))); + set_pmd(pmdp, pfn_pmd(__phys_to_pfn(phys), sect_prot)); return 1; } -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org ([198.145.29.96]:59008 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753418AbeCNIs7 (ORCPT ); Wed, 14 Mar 2018 04:48:59 -0400 From: Chintan Pandya Subject: [PATCH v1 3/4] arm64: Fix the page leak in pud/pmd_set_huge Date: Wed, 14 Mar 2018 14:18:24 +0530 Message-ID: <1521017305-28518-4-git-send-email-cpandya@codeaurora.org> In-Reply-To: <1521017305-28518-1-git-send-email-cpandya@codeaurora.org> References: <1521017305-28518-1-git-send-email-cpandya@codeaurora.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: catalin.marinas@arm.com, will.deacon@arm.com, arnd@arndb.de Cc: mark.rutland@arm.com, ard.biesheuvel@linaro.org, marc.zyngier@arm.com, james.morse@arm.com, kristina.martsenko@arm.com, takahiro.akashi@linaro.org, gregkh@linuxfoundation.org, tglx@linutronix.de, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, akpm@linux-foundation.org, toshi.kani@hpe.com, Chintan Pandya Message-ID: <20180314084824.00AH8QQpjJHkYR2lW8M5atn9d6pTkRtbW4ywiNHJLW0@z> While setting huge page, we need to take care of previously existing next level mapping. Since, we are going to overrite previous mapping, the only reference to next level page table will get lost and the next level page table will be zombie, occupying space forever. So, free it before overriding. Signed-off-by: Chintan Pandya --- arch/arm64/mm/mmu.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 8c704f1..c0df264 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -32,7 +32,7 @@ #include #include #include - +#include #include #include #include @@ -45,6 +45,7 @@ #include #include #include +#include #define NO_BLOCK_MAPPINGS BIT(0) #define NO_CONT_MAPPINGS BIT(1) @@ -939,6 +940,9 @@ int pud_set_huge(pud_t *pudp, phys_addr_t phys, pgprot_t prot) return 0; BUG_ON(phys & ~PUD_MASK); + if (pud_val(*pud) && !pud_huge(*pud)) + free_page((unsigned long)__va(pud_val(*pud))); + set_pud(pudp, pfn_pud(__phys_to_pfn(phys), sect_prot)); return 1; } @@ -953,6 +957,9 @@ int pmd_set_huge(pmd_t *pmdp, phys_addr_t phys, pgprot_t prot) return 0; BUG_ON(phys & ~PMD_MASK); + if (pmd_val(*pmd) && !pmd_huge(*pmd)) + free_page((unsigned long)__va(pmd_val(*pmd))); + set_pmd(pmdp, pfn_pmd(__phys_to_pfn(phys), sect_prot)); return 1; } -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project