selftests/bpf: Check that JMP32 pointer vs zero jumps are not predictedgrafted

Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which
the verifier used to skip, contains an out of bounds map value access,
hence w/o the previous patch the program is accepted. See previous patch
for detailed description.

Reported-by: Nicholas Carlini <npc@anthropic.com>
Suggested-by: Nicholas Carlini <npc@anthropic.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 66 insertions, 0 deletions

diff --git a/arch/alpha/Makefile b/arch/alpha/Makefile
new file mode 100644
index 000000000..7074602dc
--- /dev/null
+++ b/arch/alpha/Makefile
@@ -0,0 +1,66 @@
+#
+# alpha/Makefile
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+# Copyright (C) 1994 by Linus Torvalds
+#
+
+NM := $(NM) -B
+
+LDFLAGS_vmlinux	:= -static -N #-relax
+CHECKFLAGS	+= -D__alpha__
+cflags-y	:= -pipe -mno-fp-regs -ffixed-8
+cflags-y	+= $(call cc-option, -fno-jump-tables)
+
+cpuflags-$(CONFIG_ALPHA_EV56)		:= -mcpu=ev56
+cpuflags-$(CONFIG_ALPHA_POLARIS)	:= -mcpu=pca56
+cpuflags-$(CONFIG_ALPHA_SX164)		:= -mcpu=pca56
+cpuflags-$(CONFIG_ALPHA_EV6)		:= -mcpu=ev6
+cpuflags-$(CONFIG_ALPHA_EV67)		:= -mcpu=ev67
+# If GENERIC, make sure to turn off any instruction set extensions that
+# the host compiler might have on by default.
+cpuflags-$(CONFIG_ALPHA_GENERIC)	:= -mcpu=ev56 -mtune=ev6
+
+cflags-y				+= $(cpuflags-y)
+
+
+KBUILD_CFLAGS += $(cflags-y)
+
+# For TSUNAMI, we must have the assembler not emulate our instructions.
+# The same is true for IRONGATE, POLARIS, PYXIS.
+# BWX is most important, but we don't really want any emulation ever.
+# Only gas emulates instructions the target does not implement, and only gas
+# understands -mev6.  LLVM's integrated assembler never emulates.
+ifdef CONFIG_AS_IS_GNU
+KBUILD_CFLAGS += -Wa,-mev6
+endif
+
+libs-y				+= arch/alpha/lib/
+
+# export what is needed by arch/alpha/boot/Makefile
+LIBS_Y := $(patsubst %/, %/lib.a, $(libs-y))
+export LIBS_Y
+
+boot := arch/alpha/boot
+
+#Default target when executing make with no arguments
+all boot: $(boot)/vmlinux.gz
+
+$(boot)/vmlinux.gz: vmlinux
+	$(Q)$(MAKE) $(build)=$(boot) $@
+
+bootimage bootpfile bootpzfile: vmlinux
+	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
+
+archheaders:
+	$(Q)$(MAKE) $(build)=arch/alpha/kernel/syscalls all
+
+define archhelp
+  echo '* boot		- Compressed kernel image (arch/alpha/boot/vmlinux.gz)'
+  echo '  bootimage	- SRM bootable image (arch/alpha/boot/bootimage)'
+  echo '  bootpfile	- BOOTP bootable image (arch/alpha/boot/bootpfile)'
+  echo '  bootpzfile	- compressed kernel BOOTP image (arch/alpha/boot/bootpzfile)'
+endef