bpftool: fix potential NULL pointer dereferencing in prog_dump()

[ Upstream commit ef3ba8c258ee368a5343fa9329df85b4bcb9e8b5 ] A NULL pointer dereference could occur if ksyms is not properly checked before usage in the prog_dump() function. Fixes: b053b43 ("bpf: libbpf: bpftool: Print bpf_line_info during prog dump") Signed-off-by: Amir Mohammadi <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Acked-by: John Fastabend <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
intel · Dec 14, 2024 · 1b6341c · 1b6341c
1 parent dabaf26
commit 1b6341c
Showing 1 changed file with 12 additions and 5 deletions.
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
@@ -822,11 +822,18 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode,
 					printf("%s:\n", sym_name);
 				}
 
-				if (disasm_print_insn(img, lens[i], opcodes,
-						      name, disasm_opt, btf,
-						      prog_linfo, ksyms[i], i,
-						      linum))
-					goto exit_free;
+				if (ksyms) {
+					if (disasm_print_insn(img, lens[i], opcodes,
+							      name, disasm_opt, btf,
+							      prog_linfo, ksyms[i], i,
+							      linum))
+						goto exit_free;
+				} else {
+					if (disasm_print_insn(img, lens[i], opcodes,
+							      name, disasm_opt, btf,
+							      NULL, 0, 0, false))
+						goto exit_free;
+				}
 
 				img += lens[i];