bpf: test case for map pointer poison with calls/branches

Add several test cases where the same or different map pointers
originate from different paths in the program and execute a map
lookup or tail call at a common location.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/tools/include/linux/filter.h b/tools/include/linux/filter.h
index c5e512da8d8a..af55acf73e75 100644
--- a/tools/include/linux/filter.h
+++ b/tools/include/linux/filter.h
@@ -263,6 +263,16 @@
 #define BPF_LD_MAP_FD(DST, MAP_FD)                              \
         BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
 
+/* Relative call */
+
+#define BPF_CALL_REL(TGT)                                       \
+        ((struct bpf_insn) {                                    \
+                .code  = BPF_JMP | BPF_CALL,                    \
+                .dst_reg = 0,                                   \
+                .src_reg = BPF_PSEUDO_CALL,                     \
+                .off   = 0,                                     \
+                .imm   = TGT })
+
 /* Program exit */
 
 #define BPF_EXIT_INSN()                                         \