arm64: ptrace: Remove redundant overrun check from compat_vfp_set()

compat_vfp_set() checks for userspace trying to write an excessive
amount of data to the regset.  However this check is conspicuous
for its absence from every other _set() in the arm64 ptrace
implementation.  In fact, the core ptrace_regset() already clamps
userspace's iov_len to the regset size before the individual regset
.{get,set}() methods get called.

This patch removes the redundant check.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 4c068dc..949ab6b 100644 (file)
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -937,9 +937,6 @@ static int compat_vfp_set(struct task_struct *target,
        compat_ulong_t fpscr;
        int ret;
 
-       if (pos + count > VFP_STATE_SIZE)
-               return -EIO;
-
        uregs = &target->thread.fpsimd_state.user_fpsimd;
 
        ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,