diff options
| -rw-r--r-- | arch/powerpc/kernel/signal_32.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index a6a43103655..b13abf30599 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -941,9 +941,21 @@ long sys_swapcontext(struct ucontext __user *old_ctx, #ifdef CONFIG_PPC64 unsigned long new_msr = 0; - if (new_ctx && - get_user(new_msr, &new_ctx->uc_mcontext.mc_gregs[PT_MSR])) - return -EFAULT; + if (new_ctx) { + struct mcontext __user *mcp; + u32 cmcp; + + /* + * Get pointer to the real mcontext. No need for + * access_ok since we are dealing with compat + * pointers. + */ + if (__get_user(cmcp, &new_ctx->uc_regs)) + return -EFAULT; + mcp = (struct mcontext __user *)(u64)cmcp; + if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR])) + return -EFAULT; + } /* * Check that the context is not smaller than the original * size (with VMX but without VSX) |