4.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Ram Pai <[email protected]> commit de113256f8c1c24d8c79ae388bf2a5abd70f7577 upstream. Deny all permissions on all keys, with some exceptions. pkey-0 must allow all permissions, or else everything comes to a screaching halt. Execute-only key must allow execute permission. Fixes: cf43d3b26452 ("powerpc: Enable pkey subsystem") Cc: [email protected] # v4.16+ Signed-off-by: Ram Pai <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/powerpc/mm/pkeys.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) --- a/arch/powerpc/mm/pkeys.c +++ b/arch/powerpc/mm/pkeys.c @@ -124,12 +124,10 @@ int pkey_initialize(void) /* register mask is in BE format */ pkey_amr_mask = ~0x0ul; - pkey_iamr_mask = ~0x0ul; + pkey_amr_mask &= ~(0x3ul << pkeyshift(0)); - for (i = 0; i < (pkeys_total - os_reserved); i++) { - pkey_amr_mask &= ~(0x3ul << pkeyshift(i)); - pkey_iamr_mask &= ~(0x1ul << pkeyshift(i)); - } + pkey_iamr_mask = ~0x0ul; + pkey_iamr_mask &= ~(0x3ul << pkeyshift(0)); pkey_uamor_mask = ~0x0ul; pkey_uamor_mask &= ~(0x3ul << pkeyshift(0));
