From 537493f1460a27f81eb1499d62ec974c6103690e Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Mon, 13 Jan 2020 23:30:21 +0000 Subject: [PATCH] arm64: ptrace: nofpsimd: Fail FP/SIMD regset operations commit c9d66999f064947e6b577ceacc1eb2fbca6a8d3c upstream. When fp/simd is not supported on the system, fail the operations of FP/SIMD regsets. Fixes: 82e0191a1aa11abf ("arm64: Support systems without FP/ASIMD") Cc: Will Deacon Cc: Mark Rutland Reviewed-by: Ard Biesheuvel Reviewed-by: Catalin Marinas Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/ptrace.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 21176d02e21a..9168c4f1a37f 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -615,6 +615,13 @@ static int gpr_set(struct task_struct *target, const struct user_regset *regset, return 0; } +static int fpr_active(struct task_struct *target, const struct user_regset *regset) +{ + if (!system_supports_fpsimd()) + return -ENODEV; + return regset->n; +} + /* * TODO: update fp accessors for lazy context switching (sync/flush hwstate) */ @@ -637,6 +644,9 @@ static int fpr_get(struct task_struct *target, const struct user_regset *regset, unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf) { + if (!system_supports_fpsimd()) + return -EINVAL; + if (target == current) fpsimd_preserve_current_state(); @@ -676,6 +686,9 @@ static int fpr_set(struct task_struct *target, const struct user_regset *regset, { int ret; + if (!system_supports_fpsimd()) + return -EINVAL; + ret = __fpr_set(target, regset, pos, count, kbuf, ubuf, 0); if (ret) return ret; @@ -1134,6 +1147,7 @@ static const struct user_regset aarch64_regsets[] = { */ .size = sizeof(u32), .align = sizeof(u32), + .active = fpr_active, .get = fpr_get, .set = fpr_set }, @@ -1348,6 +1362,9 @@ static int compat_vfp_get(struct task_struct *target, compat_ulong_t fpscr; int ret, vregs_end_pos; + if (!system_supports_fpsimd()) + return -EINVAL; + uregs = &target->thread.uw.fpsimd_state; if (target == current) @@ -1381,6 +1398,9 @@ static int compat_vfp_set(struct task_struct *target, compat_ulong_t fpscr; int ret, vregs_end_pos; + if (!system_supports_fpsimd()) + return -EINVAL; + uregs = &target->thread.uw.fpsimd_state; vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t); @@ -1438,6 +1458,7 @@ static const struct user_regset aarch32_regsets[] = { .n = VFP_STATE_SIZE / sizeof(compat_ulong_t), .size = sizeof(compat_ulong_t), .align = sizeof(compat_ulong_t), + .active = fpr_active, .get = compat_vfp_get, .set = compat_vfp_set },