| From | Jiri Slaby <> | Subject | [PATCH 3.12 189/235] arm64/ptrace: Preserve previous registers for short regset write | Date | Fri, 27 Jan 2017 11:55:22 +0100 |
| |
From: Dave Martin <Dave.Martin@arm.com>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
commit 9a17b876b573441bfb3387ad55d98bf7184daf9d upstream.
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved.
Fixes: 478fcb2cdb23 ("arm64: Debugging support") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Will Deacon <Will.Deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> --- arch/arm64/kernel/ptrace.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 9b9d651446ba..076bd41bf5ac 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -487,7 +487,7 @@ static int gpr_set(struct task_struct *target, const struct user_regset *regset, const void *kbuf, const void __user *ubuf) { int ret; - struct user_pt_regs newregs; + struct user_pt_regs newregs = task_pt_regs(target)->user_regs; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1); if (ret) @@ -517,7 +517,8 @@ static int fpr_set(struct task_struct *target, const struct user_regset *regset, const void *kbuf, const void __user *ubuf) { int ret; - struct user_fpsimd_state newstate; + struct user_fpsimd_state newstate = + target->thread.fpsimd_state.user_fpsimd; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate, 0, -1); if (ret) @@ -540,7 +541,7 @@ static int tls_set(struct task_struct *target, const struct user_regset *regset, const void *kbuf, const void __user *ubuf) { int ret; - unsigned long tls; + unsigned long tls = target->thread.tp_value; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1); if (ret) -- 2.11.0
|