From d21001cc15ba9f63b0334d60942278587471a451 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf <jpoimboe@redhat.com> Date: Thu, 21 Jan 2016 16:49:27 -0600 Subject: [PATCH] x86/asm/bpf: Create stack frames in bpf_jit.S bpf_jit.S has several callable non-leaf functions which don't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create a stack frame before the call instructions when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/fa4c41976b438b51954cb8021f06bceb1d1d66cc.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- arch/x86/net/bpf_jit.S | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/net/bpf_jit.S b/arch/x86/net/bpf_jit.S index eb4a3bd293eb7..f2a7faf4706eb 100644 --- a/arch/x86/net/bpf_jit.S +++ b/arch/x86/net/bpf_jit.S @@ -8,6 +8,7 @@ * of the License. */ #include <linux/linkage.h> +#include <asm/frame.h> /* * Calling convention : @@ -65,16 +66,18 @@ FUNC(sk_load_byte_positive_offset) /* rsi contains offset and can be scratched */ #define bpf_slow_path_common(LEN) \ + lea -MAX_BPF_STACK + 32(%rbp), %rdx;\ + FRAME_BEGIN; \ mov %rbx, %rdi; /* arg1 == skb */ \ push %r9; \ push SKBDATA; \ /* rsi already has offset */ \ mov $LEN,%ecx; /* len */ \ - lea - MAX_BPF_STACK + 32(%rbp),%rdx; \ call skb_copy_bits; \ test %eax,%eax; \ pop SKBDATA; \ - pop %r9; + pop %r9; \ + FRAME_END bpf_slow_path_word: @@ -99,6 +102,7 @@ bpf_slow_path_byte: ret #define sk_negative_common(SIZE) \ + FRAME_BEGIN; \ mov %rbx, %rdi; /* arg1 == skb */ \ push %r9; \ push SKBDATA; \ @@ -108,6 +112,7 @@ bpf_slow_path_byte: test %rax,%rax; \ pop SKBDATA; \ pop %r9; \ + FRAME_END; \ jz bpf_error bpf_slow_path_word_neg: -- GitLab