diff options
| author | Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> | 2020-07-09 08:59:42 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-07-20 22:57:59 +1000 |
| commit | e0d8e991be641ba0034c67785bf86f6c097869d6 (patch) | |
| tree | 608b14a2b1c2097b199ad995f8ca8b151e120321 /arch/powerpc/kernel | |
| parent | 000a42b35a54372597f0657f6b9875b38c641864 (diff) | |
powerpc/book3s64/kuap: Move UAMOR setup to key init function
UAMOR values are not application-specific. The kernel initializes
its value based on different reserved keys. Remove the thread-specific
UAMOR value and don't switch the UAMOR on context switch.
Move UAMOR initialization to key initialization code and remove
thread_struct.uamor because it is not used anymore.
Before commit: 4a4a5e5d2aad ("powerpc/pkeys: key allocation/deallocation must not change pkey registers")
we used to update uamor based on key allocation and free.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709032946.881753-20-aneesh.kumar@linux.ibm.com
Diffstat (limited to 'arch/powerpc/kernel')
| -rw-r--r-- | arch/powerpc/kernel/ptrace/ptrace-view.c | 27 | ||||
| -rw-r--r-- | arch/powerpc/kernel/smp.c | 1 |
2 files changed, 22 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/ptrace/ptrace-view.c b/arch/powerpc/kernel/ptrace/ptrace-view.c index caeb5822a8f4..ac7d480cb9c1 100644 --- a/arch/powerpc/kernel/ptrace/ptrace-view.c +++ b/arch/powerpc/kernel/ptrace/ptrace-view.c @@ -488,14 +488,21 @@ static int pkey_active(struct task_struct *target, const struct user_regset *reg static int pkey_get(struct task_struct *target, const struct user_regset *regset, unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf) { + int ret; + BUILD_BUG_ON(TSO(amr) + sizeof(unsigned long) != TSO(iamr)); - BUILD_BUG_ON(TSO(iamr) + sizeof(unsigned long) != TSO(uamor)); if (!arch_pkeys_enabled()) return -ENODEV; - return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.amr, - 0, ELF_NPKEY * sizeof(unsigned long)); + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.amr, + 0, 2 * sizeof(unsigned long)); + if (ret) + return ret; + + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &default_uamor, + 2 * sizeof(unsigned long), 3 * sizeof(unsigned long)); + return ret; } static int pkey_set(struct task_struct *target, const struct user_regset *regset, @@ -517,9 +524,17 @@ static int pkey_set(struct task_struct *target, const struct user_regset *regset if (ret) return ret; - /* UAMOR determines which bits of the AMR can be set from userspace. */ - target->thread.amr = (new_amr & target->thread.uamor) | - (target->thread.amr & ~target->thread.uamor); + /* + * UAMOR determines which bits of the AMR can be set from userspace. + * UAMOR value 0b11 indicates that the AMR value can be modified + * from userspace. If the kernel is using a specific key, we avoid + * userspace modifying the AMR value for that key by masking them + * via UAMOR 0b00. + * + * Pick the AMR values for the keys that kernel is using. This + * will be indicated by the ~default_uamor bits. + */ + target->thread.amr = (new_amr & default_uamor) | (target->thread.amr & ~default_uamor); return 0; } diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 73199470c265..8261999c7d52 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -59,6 +59,7 @@ #include <asm/asm-prototypes.h> #include <asm/cpu_has_feature.h> #include <asm/ftrace.h> +#include <asm/kup.h> #ifdef DEBUG #include <asm/udbg.h> |