Linux patch 4.4.264.4-28

2 files changed, 157 insertions, 0 deletions

diff --git a/0000_README b/0000_README
index 8be42943..1d64ed05 100644
--- a/0000_README
+++ b/0000_README
@@ -143,6 +143,10 @@ Patch:  1024_linux-4.4.25.patch
 From:   http://www.kernel.org
 Desc:   Linux 4.4.25
 
+Patch:  1025_linux-4.4.26.patch
+From:   http://www.kernel.org
+Desc:   Linux 4.4.26
+
 Patch:  1500_XATTR_USER_PREFIX.patch
 From:   https://bugs.gentoo.org/show_bug.cgi?id=470644
 Desc:   Support for namespace user.pax.* on tmpfs.
diff --git a/1025_linux-4.4.26.patch b/1025_linux-4.4.26.patch
new file mode 100644
index 00000000..f09375b0
--- /dev/null
+++ b/1025_linux-4.4.26.patch
@@ -0,0 +1,153 @@
+diff --git a/Makefile b/Makefile
+index 578a82554923..a127b9ef9ebc 100644
+--- a/Makefile
++++ b/Makefile
+@@ -1,6 +1,6 @@
+ VERSION = 4
+ PATCHLEVEL = 4
+-SUBLEVEL = 25
++SUBLEVEL = 26
+ EXTRAVERSION =
+ NAME = Blurry Fish Butt
+ 
+diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
+index 0a291cdfaf77..efa6073ffa7e 100644
+--- a/arch/x86/boot/compressed/Makefile
++++ b/arch/x86/boot/compressed/Makefile
+@@ -22,7 +22,7 @@ targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
+ 	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
+ 
+ KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2
+-KBUILD_CFLAGS += -fno-strict-aliasing -fPIC
++KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC)
+ KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
+ cflags-$(CONFIG_X86_32) := -march=i386
+ cflags-$(CONFIG_X86_64) := -mcmodel=small
+@@ -35,6 +35,18 @@ KBUILD_AFLAGS  := $(KBUILD_CFLAGS) -D__ASSEMBLY__
+ GCOV_PROFILE := n
+ 
+ LDFLAGS := -m elf_$(UTS_MACHINE)
++ifeq ($(CONFIG_RELOCATABLE),y)
++# If kernel is relocatable, build compressed kernel as PIE.
++ifeq ($(CONFIG_X86_32),y)
++LDFLAGS += $(call ld-option, -pie) $(call ld-option, --no-dynamic-linker)
++else
++# To build 64-bit compressed kernel as PIE, we disable relocation
++# overflow check to avoid relocation overflow error with a new linker
++# command-line option, -z noreloc-overflow.
++LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \
++	&& echo "-z noreloc-overflow -pie --no-dynamic-linker")
++endif
++endif
+ LDFLAGS_vmlinux := -T
+ 
+ hostprogs-y	:= mkpiggy
+diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
+index 8ef964ddc18e..0256064da8da 100644
+--- a/arch/x86/boot/compressed/head_32.S
++++ b/arch/x86/boot/compressed/head_32.S
+@@ -31,6 +31,34 @@
+ #include <asm/asm-offsets.h>
+ #include <asm/bootparam.h>
+ 
++/*
++ * The 32-bit x86 assembler in binutils 2.26 will generate R_386_GOT32X
++ * relocation to get the symbol address in PIC.  When the compressed x86
++ * kernel isn't built as PIC, the linker optimizes R_386_GOT32X
++ * relocations to their fixed symbol addresses.  However, when the
++ * compressed x86 kernel is loaded at a different address, it leads
++ * to the following load failure:
++ *
++ *   Failed to allocate space for phdrs
++ *
++ * during the decompression stage.
++ *
++ * If the compressed x86 kernel is relocatable at run-time, it should be
++ * compiled with -fPIE, instead of -fPIC, if possible and should be built as
++ * Position Independent Executable (PIE) so that linker won't optimize
++ * R_386_GOT32X relocation to its fixed symbol address.  Older
++ * linkers generate R_386_32 relocations against locally defined symbols,
++ * _bss, _ebss, _got and _egot, in PIE.  It isn't wrong, just less
++ * optimal than R_386_RELATIVE.  But the x86 kernel fails to properly handle
++ * R_386_32 relocations when relocating the kernel.  To generate
++ * R_386_RELATIVE relocations, we mark _bss, _ebss, _got and _egot as
++ * hidden:
++ */
++	.hidden _bss
++	.hidden _ebss
++	.hidden _got
++	.hidden _egot
++
+ 	__HEAD
+ ENTRY(startup_32)
+ #ifdef CONFIG_EFI_STUB
+diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
+index b0c0d16ef58d..86558a199139 100644
+--- a/arch/x86/boot/compressed/head_64.S
++++ b/arch/x86/boot/compressed/head_64.S
+@@ -33,6 +33,14 @@
+ #include <asm/asm-offsets.h>
+ #include <asm/bootparam.h>
+ 
++/*
++ * Locally defined symbols should be marked hidden:
++ */
++	.hidden _bss
++	.hidden _ebss
++	.hidden _got
++	.hidden _egot
++
+ 	__HEAD
+ 	.code32
+ ENTRY(startup_32)
+diff --git a/include/linux/mm.h b/include/linux/mm.h
+index cfebb742ee18..f0ffa01c90d9 100644
+--- a/include/linux/mm.h
++++ b/include/linux/mm.h
+@@ -2112,6 +2112,7 @@ static inline struct page *follow_page(struct vm_area_struct *vma,
+ #define FOLL_MIGRATION	0x400	/* wait for page to replace migration entry */
+ #define FOLL_TRIED	0x800	/* a retry, previous pass started an IO */
+ #define FOLL_MLOCK	0x1000	/* lock present pages */
++#define FOLL_COW	0x4000	/* internal GUP flag */
+ 
+ typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
+ 			void *data);
+diff --git a/mm/gup.c b/mm/gup.c
+index deafa2c91b36..4b0b7e7d1136 100644
+--- a/mm/gup.c
++++ b/mm/gup.c
+@@ -58,6 +58,16 @@ static int follow_pfn_pte(struct vm_area_struct *vma, unsigned long address,
+ 	return -EEXIST;
+ }
+ 
++/*
++ * FOLL_FORCE can write to even unwritable pte's, but only
++ * after we've gone through a COW cycle and they are dirty.
++ */
++static inline bool can_follow_write_pte(pte_t pte, unsigned int flags)
++{
++	return pte_write(pte) ||
++		((flags & FOLL_FORCE) && (flags & FOLL_COW) && pte_dirty(pte));
++}
++
+ static struct page *follow_page_pte(struct vm_area_struct *vma,
+ 		unsigned long address, pmd_t *pmd, unsigned int flags)
+ {
+@@ -92,7 +102,7 @@ retry:
+ 	}
+ 	if ((flags & FOLL_NUMA) && pte_protnone(pte))
+ 		goto no_page;
+-	if ((flags & FOLL_WRITE) && !pte_write(pte)) {
++	if ((flags & FOLL_WRITE) && !can_follow_write_pte(pte, flags)) {
+ 		pte_unmap_unlock(ptep, ptl);
+ 		return NULL;
+ 	}
+@@ -352,7 +362,7 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma,
+ 	 * reCOWed by userspace write).
+ 	 */
+ 	if ((ret & VM_FAULT_WRITE) && !(vma->vm_flags & VM_WRITE))
+-		*flags &= ~FOLL_WRITE;
++	        *flags |= FOLL_COW;
+ 	return 0;
+ }
+