From 3e4352aeb8b17eb1040ba288f586620e8294389d Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Thu, 9 Jul 2020 08:59:35 +0530 Subject: [PATCH] powerpc/book3s64/pkeys: Mark all the pkeys above max pkey as reserved The hypervisor can return less than max allowed pkey (for ex: 31) instead of 32. We should mark all the pkeys above max allowed as reserved so that we avoid the allocation of the wrong pkey(for ex: key 31 in the above case) by userspace. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200709032946.881753-13-aneesh.kumar@linux.ibm.com --- arch/powerpc/mm/book3s64/pkeys.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c index e9fd0db..d84bf55 100644 --- a/arch/powerpc/mm/book3s64/pkeys.c +++ b/arch/powerpc/mm/book3s64/pkeys.c @@ -189,9 +189,10 @@ static int pkey_initialize(void) /* * Prevent the usage of OS reserved keys. Update UAMOR - * for those keys. + * for those keys. Also mark the rest of the bits in the + * 32 bit mask as reserved. */ - for (i = num_pkey; i < pkeys_total; i++) { + for (i = num_pkey; i < 32 ; i++) { reserved_allocation_mask |= (0x1 << i); default_uamor &= ~(0x3ul << pkeyshift(i)); } -- 2.7.4