From 2227901a0230d8fde81ba9c602d649839390f56b Mon Sep 17 00:00:00 2001 From: Victor Kamensky Date: Tue, 3 Jun 2014 19:21:30 +0100 Subject: [PATCH] arm64: ptrace: fix empty registers set in prstatus of aarch32 process core Currently core file of aarch32 process prstatus note has empty registers set. As result aarch32 core files create by V8 kernel are not very useful. It happens because compat_gpr_get and compat_gpr_set functions can copy registers values to/from either kbuf or ubuf. ELF core file collection function fill_thread_core_info calls compat_gpr_get with kbuf set and ubuf set to 0. But current compat_gpr_get and compat_gpr_set function handle copy to/from only ubuf case. Fix is to handle kbuf and ubuf as two separate cases in similar way as other functions like user_regset_copyout, user_regset_copyin do. Signed-off-by: Victor Kamensky Acked-by: Will Deacon Cc: stable@vger.kernel.org Signed-off-by: Catalin Marinas --- arch/arm64/kernel/ptrace.c | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 993cdb79b70e..9fde010c945f 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -655,11 +655,16 @@ static int compat_gpr_get(struct task_struct *target, reg = task_pt_regs(target)->regs[idx]; } - ret = copy_to_user(ubuf, ®, sizeof(reg)); - if (ret) - break; - - ubuf += sizeof(reg); + if (kbuf) { + memcpy(kbuf, ®, sizeof(reg)); + kbuf += sizeof(reg); + } else { + ret = copy_to_user(ubuf, ®, sizeof(reg)); + if (ret) + break; + + ubuf += sizeof(reg); + } } return ret; @@ -689,11 +694,16 @@ static int compat_gpr_set(struct task_struct *target, unsigned int idx = start + i; compat_ulong_t reg; - ret = copy_from_user(®, ubuf, sizeof(reg)); - if (ret) - return ret; + if (kbuf) { + memcpy(®, kbuf, sizeof(reg)); + kbuf += sizeof(reg); + } else { + ret = copy_from_user(®, ubuf, sizeof(reg)); + if (ret) + return ret; - ubuf += sizeof(reg); + ubuf += sizeof(reg); + } switch (idx) { case 15: -- 2.20.1