[PATCH 3.12 42/63] KVM: ARM/arm64: avoid returning negative error code as bool

From: Jiri Slaby
Date: Thu Apr 30 2015 - 08:23:02 EST


From: Will Deacon <will.deacon@xxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 18d457661fb9fa69352822ab98d39331c3d0e571 upstream.

is_valid_cache returns true if the specified cache is valid.
Unfortunately, if the parameter passed it out of range, we return
-ENOENT, which ends up as true leading to potential hilarity.

This patch returns false on the failure path instead.

Cc: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
Signed-off-by: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
arch/arm/kvm/coproc.c | 2 +-
arch/arm64/kvm/sys_regs.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 24edbdea617e..4dc9256d48a3 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -621,7 +621,7 @@ static bool is_valid_cache(u32 val)
u32 level, ctype;

if (val >= CSSELR_MAX)
- return -ENOENT;
+ return false;

/* Bottom bit is Instruction or Data bit. Next 3 bits are level. */
level = (val >> 1);
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 5ee99e43890a..7691b2563d27 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -836,7 +836,7 @@ static bool is_valid_cache(u32 val)
u32 level, ctype;

if (val >= CSSELR_MAX)
- return -ENOENT;
+ return false;

/* Bottom bit is Instruction or Data bit. Next 3 bits are level. */
level = (val >> 1);
--
2.3.5

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