From: Dave Martin <Dave.Martin@xxxxxxx>
[ Upstream commit 5fbd5fc49fc39ac8433da62d16682a1d0217ea4f ]
Now that compat_vfp_get() uses the regset API to copy the FPSCR
value out to userspace, compat_vfp_set() looks inconsistent. In
particular, compat_vfp_set() will fail if called with kbuf != NULL
&& ubuf == NULL (which is valid usage according to the regset API).
This patch fixes compat_vfp_set() to use user_regset_copyin(),
similarly to compat_vfp_get().
This also squashes a sparse warning triggered by the cast that
drops __user when calling get_user().
Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
arch/arm64/kernel/ptrace.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index b81fa63bc834..f67bb64d2640 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -822,18 +822,20 @@ static int compat_vfp_set(struct task_struct *target,
{
struct user_fpsimd_state *uregs;
compat_ulong_t fpscr;
- int ret;
+ int ret, vregs_end_pos;
if (pos + count > VFP_STATE_SIZE)
return -EIO;
uregs = &target->thread.fpsimd_state.user_fpsimd;
+ vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
- VFP_STATE_SIZE - sizeof(compat_ulong_t));
+ vregs_end_pos);
if (count && !ret) {
- ret = get_user(fpscr, (compat_ulong_t *)ubuf);
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpscr,
+ vregs_end_pos, VFP_STATE_SIZE);
if (!ret) {
uregs->fpsr = fpscr & VFP_FPSCR_STAT_MASK;
uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
--
2.15.1