From 0ab32b6f1b88444524e52429fab334ff96683a3f Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Thu, 5 Nov 2015 18:46:03 -0800 Subject: uaccess: reimplement probe_kernel_address() using probe_kernel_read() probe_kernel_address() is basically the same as the (later added) probe_kernel_read(). The return value on EFAULT is a bit different: probe_kernel_address() returns number-of-bytes-not-copied whereas probe_kernel_read() returns -EFAULT. All callers have been checked, none cared. probe_kernel_read() can be overridden by the architecture whereas probe_kernel_address() cannot. parisc, blackfin and um do this, to insert additional checking. Hence this patch possibly fixes obscure bugs, although there are only two probe_kernel_address() callsites outside arch/. My first attempt involved removing probe_kernel_address() entirely and converting all callsites to use probe_kernel_read() directly, but that got tiresome. This patch shrinks mm/slab_common.o by 218 bytes. For a single probe_kernel_address() callsite. Cc: Steven Miao Cc: Jeff Dike Cc: Richard Weinberger Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/powerpc/sysdev/fsl_pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/powerpc/sysdev/fsl_pci.c') diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c index ebc1f412cf49..13b9bcf5485e 100644 --- a/arch/powerpc/sysdev/fsl_pci.c +++ b/arch/powerpc/sysdev/fsl_pci.c @@ -999,7 +999,7 @@ int fsl_pci_mcheck_exception(struct pt_regs *regs) ret = get_user(regs->nip, &inst); pagefault_enable(); } else { - ret = probe_kernel_address(regs->nip, inst); + ret = probe_kernel_address((void *)regs->nip, inst); } if (mcheck_handle_load(regs, inst)) { -- cgit