x86/mm: Stop printing BRK addresses

nivedita76 · suryasaimadhu · commit 67d631b7c05e · 2020-05-23T09:34:18.000+02:00
This currently leaks kernel physical addresses into userspace. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Dave Hansen <dave.hansen@intel.com> Link: https://lkml.kernel.org/r/20200229231120.1147527-1-nivedita@alum.mit.edu
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
@@ -121,8 +121,6 @@ __ref void *alloc_low_pages(unsigned int num)
 	} else {
 		pfn = pgt_buf_end;
 		pgt_buf_end += num;
-		printk(KERN_DEBUG "BRK [%#010lx, %#010lx] PGTABLE\n",
-			pfn << PAGE_SHIFT, (pgt_buf_end << PAGE_SHIFT) - 1);
 	}
 
 	for (i = 0; i < num; i++) {

Original file line number	Diff line number	Diff line change
`@@ -121,8 +121,6 @@ __ref void *alloc_low_pages(unsigned int num)`
`121`	`121`	`} else {`
`122`	`122`	`pfn = pgt_buf_end;`
`123`	`123`	`pgt_buf_end += num;`
`124`		`- printk(KERN_DEBUG "BRK [%#010lx, %#010lx] PGTABLE\n",`
`125`		`- pfn << PAGE_SHIFT, (pgt_buf_end << PAGE_SHIFT) - 1);`
`126`	`124`	`}`
`127`	`125`
`128`	`126`	`for (i = 0; i < num; i++) {`