From: David Woodhouse Date: Thu, 24 Nov 2005 12:51:40 +0000 (+0000) Subject: [PATCH] Save NVGPRS in 32-bit signal frame X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=9687c587596b54a77f08620595f5686ea35eed97;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git [PATCH] Save NVGPRS in 32-bit signal frame Somehow this one slipped through the cracks; when we ended up in do_signal() on a 32-bit kernel but without having the caller-saved registers into the regs, we didn't set the TIF_SAVE_NVGPRS flag to ensure they got saved later. Signed-off-by: David Woodhouse Signed-off-by: Paul Mackerras --- diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index c9d02751127f..d3f0b6d452fb 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -219,6 +219,15 @@ static inline int get_old_sigaction(struct k_sigaction *new_ka, static inline int save_general_regs(struct pt_regs *regs, struct mcontext __user *frame) { + if (!FULL_REGS(regs)) { + /* Zero out the unsaved GPRs to avoid information + leak, and set TIF_SAVE_NVGPRS to ensure that the + registers do actually get saved later. */ + memset(®s->gpr[14], 0, 18 * sizeof(unsigned long)); + current_thread_info()->nvgprs_frame = &frame->mc_gregs; + set_thread_flag(TIF_SAVE_NVGPRS); + } + return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE); }