From 595c259f75aeb0114014dc1cd6c54f9c9feee25c Mon Sep 17 00:00:00 2001 From: Eliav Farber <farbere@amazon.com> Date: Thu, 13 Jan 2022 10:06:19 +0000 Subject: [PATCH] EDAC: Fix calculation of returned address and next offset in edac_align_ptr() commit f8efca92ae509c25e0a4bd5d0a86decea4f0c41e upstream. Do alignment logic properly and use the "ptr" local variable for calculating the remainder of the alignment. This became an issue because struct edac_mc_layer has a size that is not zero modulo eight, and the next offset that was prepared for the private data was unaligned, causing an alignment exception. The patch in Fixes: which broke this actually wanted to "what we actually care about is the alignment of the actual pointer that's about to be returned." But it didn't check that alignment. Use the correct variable "ptr" for that. [ bp: Massage commit message. ] Fixes: 8447c4d15e35 ("edac: Do alignment logic properly in edac_align_ptr()") Signed-off-by: Eliav Farber <farbere@amazon.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220113100622.12783-2-farbere@amazon.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/edac/edac_mc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c index 01ff71f7b6456..f4eb071327be0 100644 --- a/drivers/edac/edac_mc.c +++ b/drivers/edac/edac_mc.c @@ -210,7 +210,7 @@ void *edac_align_ptr(void **p, unsigned int size, int n_elems) else return (char *)ptr; - r = (unsigned long)p % align; + r = (unsigned long)ptr % align; if (r == 0) return (char *)ptr;