Rebase 4.18.9 patches onto 4.18.10

Makefile

@@ -143,7 +143,8 @@ $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
 
 # Invoke a second make in the output directory, passing relevant variables
 sub-make:
-	$(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
+	$(Q)$(MAKE) -C $(KBUILD_OUTPUT) \
+	KBUILD_SRC=$(shell realpath --relative-to=$(KBUILD_OUTPUT) $(CURDIR)) \
 	-f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
 
 # Leave processing to above invocation of make

arch/x86/boot/compressed/Makefile

@@ -42,16 +42,16 @@ KBUILD_AFLAGS  := $(KBUILD_CFLAGS) -D__ASSEMBLY__
 GCOV_PROFILE := n
 UBSAN_SANITIZE :=n
 
-LDFLAGS := -m elf_$(UTS_MACHINE)
+override LDFLAGS := -m elf_$(UTS_MACHINE)
 # Compressed kernel should be built as PIE since it may be loaded at any
 # address by the bootloader.
 ifeq ($(CONFIG_X86_32),y)
-LDFLAGS += $(call ld-option, -pie) $(call ld-option, --no-dynamic-linker)
+override 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" \
+override LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \
 	&& echo "-z noreloc-overflow -pie --no-dynamic-linker")
 endif
 LDFLAGS_vmlinux := -T

include/net/ipv6.h

@@ -373,8 +373,8 @@ static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 	    idev->cnf.accept_ra;
 }
 
-#define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
-#define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
+#define IPV6_FRAG_HIGH_THRESH	(256 * 1024)	/* 262144 */
+#define IPV6_FRAG_LOW_THRESH	(192 * 1024)	/* 196608 */
 #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
 
 int __ipv6_addr_type(const struct in6_addr *addr);

net/ipv4/ip_fragment.c

@@ -788,22 +788,14 @@ static int __net_init ipv4_frags_init_net(struct net *net)
 {
 	int res;
 
-	/* Fragment cache limits.
-	 *
-	 * The fragment memory accounting code, (tries to) account for
-	 * the real memory usage, by measuring both the size of frag
-	 * queue struct (inet_frag_queue (ipv4:ipq/ipv6:frag_queue))
-	 * and the SKB's truesize.
-	 *
-	 * A 64K fragment consumes 129736 bytes (44*2944)+200
-	 * (1500 truesize == 2944, sizeof(struct ipq) == 200)
-	 *
-	 * We will commit 4MB at one time. Should we cross that limit
-	 * we will prune down to 3MB, making room for approx 8 big 64K
-	 * fragments 8x128k.
+	/*
+	 * Fragment cache limits. We will commit 256K at one time. Should we
+	 * cross that limit we will prune down to 192K. This should cope with
+	 * even the most extreme cases without allowing an attacker to
+	 * measurably harm machine performance.
 	 */
-	net->ipv4.frags.high_thresh = 4 * 1024 * 1024;
-	net->ipv4.frags.low_thresh  = 3 * 1024 * 1024;
+	net->ipv4.frags.high_thresh = 256 * 1024;
+	net->ipv4.frags.low_thresh = 192 * 1024;
 	/*
 	 * Important NOTE! Fragment queue must be destroyed before MSL expires.
 	 * RFC791 is wrong proposing to prolongate timer each fragment arrival

tools/lib/subcmd/Makefile

@@ -33,6 +33,9 @@ ifneq ($(WERROR),0)
   CFLAGS += -Werror
 endif
 
+# Don't fail on fallthrough with newer GCCs.
+CFLAGS += -Wno-error=implicit-fallthrough
+
 CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE
 
 CFLAGS += -I$(srctree)/tools/include/