[patch] hardened1 patches that trigger BUG

5-15-85-hardened-nomemory.patch (text/plain), 5.58 KB, created by genBTC on 2023-01-07 09:14:15 UTC

diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 1000d457c3321..18d38955bc20a 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -298,55 +298,9 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
 }
 
 #ifdef CONFIG_X86_64
-/*
- * Put the vdso above the (randomized) stack with another randomized
- * offset.  This way there is no hole in the middle of address space.
- * To save memory make sure it is still in the same PTE as the stack
- * top.  This doesn't give that many random bits.
- *
- * Note that this algorithm is imperfect: the distribution of the vdso
- * start address within a PMD is biased toward the end.
- *
- * Only used for the 64-bit and x32 vdsos.
- */
-static unsigned long vdso_addr(unsigned long start, unsigned len)
-{
-	unsigned long addr, end;
-	unsigned offset;
-
-	/*
-	 * Round up the start address.  It can start out unaligned as a result
-	 * of stack start randomization.
-	 */
-	start = PAGE_ALIGN(start);
-
-	/* Round the lowest possible end address up to a PMD boundary. */
-	end = (start + len + PMD_SIZE - 1) & PMD_MASK;
-	if (end >= TASK_SIZE_MAX)
-		end = TASK_SIZE_MAX;
-	end -= len;
-
-	if (end > start) {
-		offset = get_random_int() % (((end - start) >> PAGE_SHIFT) + 1);
-		addr = start + (offset << PAGE_SHIFT);
-	} else {
-		addr = start;
-	}
-
-	/*
-	 * Forcibly align the final address in case we have a hardware
-	 * issue that requires alignment for performance reasons.
-	 */
-	addr = align_vdso_addr(addr);
-
-	return addr;
-}
-
 static int map_vdso_randomized(const struct vdso_image *image)
 {
-	unsigned long addr = vdso_addr(current->mm->start_stack, image->size-image->sym_vvar_start);
-
-	return map_vdso(image, addr);
+	return map_vdso(image, 0);
 }
 #endif
 
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index 29fea180a6658..28d86671b089a 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -247,11 +247,11 @@ extern int force_personality32;
 
 /*
  * This is the base location for PIE (ET_DYN with INTERP) loads. On
- * 64-bit, this is above 4GB to leave the entire 32-bit address
+ * 64-bit, this is raised to 4GB to leave the entire 32-bit address
  * space open for things that want to use the area for 32-bit pointers.
  */
 #define ELF_ET_DYN_BASE		(mmap_is_ia32() ? 0x000400000UL : \
-						  (DEFAULT_MAP_WINDOW / 3 * 2))
+						  0x100000000UL)
 
 /* This yields a mask that user programs can use to figure out what
    instruction set this CPU supports.  This could be done in user space,
@@ -333,8 +333,8 @@ extern unsigned long get_sigframe_size(void);
 
 #ifdef CONFIG_X86_32
 
-#define __STACK_RND_MASK(is32bit) (0x7ff)
-#define STACK_RND_MASK (0x7ff)
+#define __STACK_RND_MASK(is32bit) ((1UL << mmap_rnd_bits) - 1)
+#define STACK_RND_MASK ((1UL << mmap_rnd_bits) - 1)
 
 #define ARCH_DLINFO		ARCH_DLINFO_IA32
 
@@ -343,7 +343,11 @@ extern unsigned long get_sigframe_size(void);
 #else /* CONFIG_X86_32 */
 
 /* 1GB for 64bit, 8MB for 32bit */
-#define __STACK_RND_MASK(is32bit) ((is32bit) ? 0x7ff : 0x3fffff)
+#ifdef CONFIG_COMPAT
+#define __STACK_RND_MASK(is32bit) ((is32bit) ? (1UL << mmap_rnd_compat_bits) - 1 : (1UL << mmap_rnd_bits) - 1)
+#else
+#define __STACK_RND_MASK(is32bit) ((1UL << mmap_rnd_bits) - 1)
+#endif
 #define STACK_RND_MASK __STACK_RND_MASK(mmap_is_ia32())
 
 #define ARCH_DLINFO							\
@@ -407,5 +411,4 @@ struct va_alignment {
 } ____cacheline_aligned;
 
 extern struct va_alignment va_align;
-extern unsigned long align_vdso_addr(unsigned long);
 #endif /* _ASM_X86_ELF_H */
265a375,446
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index bc9b4b93cf9bc..76f2bd6012e57 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -43,6 +43,8 @@
 #include <asm/io_bitmap.h>
 #include <asm/proto.h>
 #include <asm/frame.h>
+#include <asm/elf.h>
+#include <linux/sizes.h>
 
 #include "process.h"
 
@@ -625,6 +627,7 @@ void speculation_ctrl_update_current(void)
 static inline void cr4_toggle_bits_irqsoff(unsigned long mask)
 {
 	unsigned long newval, cr4 = this_cpu_read(cpu_tlbstate.cr4);
+	BUG_ON(cr4 != __read_cr4());
 
 	newval = cr4 ^ mask;
 	if (newval != cr4) {
@@ -937,7 +940,10 @@ unsigned long arch_align_stack(unsigned long sp)
 
 unsigned long arch_randomize_brk(struct mm_struct *mm)
 {
-	return randomize_page(mm->brk, 0x02000000);
+	if (mmap_is_ia32())
+		return mm->brk + get_random_long() % SZ_32M + PAGE_SIZE;
+	else
+		return mm->brk + get_random_long() % SZ_1G + PAGE_SIZE;
 }
 
 /*
diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c
index 8cc653ffdccd7..77e8a88ba3b31 100644
--- a/arch/x86/kernel/sys_x86_64.c
+++ b/arch/x86/kernel/sys_x86_64.c
@@ -52,13 +52,6 @@ static unsigned long get_align_bits(void)
 	return va_align.bits & get_align_mask();
 }
 
-unsigned long align_vdso_addr(unsigned long addr)
-{
-	unsigned long align_mask = get_align_mask();
-	addr = (addr + align_mask) & ~align_mask;
-	return addr | get_align_bits();
-}
-
 static int __init control_va_addr_alignment(char *str)
 {
 	/* guard against enabling this on other CPU families */
@@ -113,10 +106,7 @@ static void find_start_end(unsigned long addr, unsigned long flags,
 	}
 
 	*begin	= get_mmap_base(1);
-	if (in_32bit_syscall())
-		*end = task_size_32bit();
-	else
-		*end = task_size_64bit(addr > DEFAULT_MAP_WINDOW);
+	*end	= get_mmap_base(0);
 }
 
 unsigned long
@@ -193,7 +183,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 
 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 	info.length = len;
-	info.low_limit = PAGE_SIZE;
+	info.low_limit = get_mmap_base(1);
 	info.high_limit = get_mmap_base(0);
 
 	/*