linux-kernel - [PATCH 2/4] ARM: use a temporary variable to hold maximum vmalloc size

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 18 May 2021 13:15:45 +0100
From:   "Russell King (Oracle)" <rmk+kernel@...linux.org.uk>
To:     Yanfei Xu <yanfei.xu@...driver.com>
Cc:     rppt@...nel.org, ardb@...nel.org, linus.walleij@...aro.org,
        akpm@...ux-foundation.org, carver4lio@....com,
        tiantao6@...ilicon.com, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 2/4] ARM: use a temporary variable to hold maximum vmalloc
 size

We calculate the maximum size of the vmalloc space twice in
early_vmalloc(). Use a temporary variable to hold this value.

Signed-off-by: Russell King (Oracle) <rmk+kernel@...linux.org.uk>
---
 arch/arm/mm/mmu.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 206c345f063e..d932c46a02e0 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1134,6 +1134,7 @@ static unsigned long __initdata vmalloc_min =
 static int __init early_vmalloc(char *arg)
 {
 	unsigned long vmalloc_reserve = memparse(arg, NULL);
+	unsigned long vmalloc_max;
 
 	if (vmalloc_reserve < SZ_16M) {
 		vmalloc_reserve = SZ_16M;
@@ -1141,8 +1142,9 @@ static int __init early_vmalloc(char *arg)
 			vmalloc_reserve >> 20);
 	}
 
-	if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
-		vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
+	vmalloc_max = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
+	if (vmalloc_reserve > vmalloc_max) {
+		vmalloc_reserve = vmalloc_max;
 		pr_warn("vmalloc area is too big, limiting to %luMB\n",
 			vmalloc_reserve >> 20);
 	}
-- 
2.20.1