From 286aad3c4014ca825c447e07e24f8929e6d266d2 Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <dborkman@redhat.com>
Date: Mon, 8 Sep 2014 08:04:49 +0200
Subject: [PATCH] net: bpf: be friendly to kmemcheck
Reported by Mikulas Patocka, kmemcheck currently barks out a
false positive since we don't have special kmemcheck annotation
for bitfields used in bpf_prog structure.
We currently have jited:1, len:31 and thus when accessing len
while CONFIG_KMEMCHECK enabled, kmemcheck throws a warning that
we're reading uninitialized memory.
As we don't need the whole bit universe for pages member, we
can just split it to u16 and use a bool flag for jited instead
of a bitfield.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
arch/arm/net/bpf_jit_32.c | 2 +-
arch/mips/net/bpf_jit.c | 2 +-
arch/powerpc/net/bpf_jit_comp.c | 2 +-
arch/s390/net/bpf_jit_comp.c | 2 +-
arch/sparc/net/bpf_jit_comp.c | 2 +-
arch/x86/net/bpf_jit_comp.c | 2 +-
include/linux/filter.h | 6 +++---
net/core/filter.c | 2 +-
8 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index 2d1a5b93d91c5..6b45f649eff0c 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -933,7 +933,7 @@ void bpf_jit_compile(struct bpf_prog *fp)
set_memory_ro((unsigned long)header, header->pages);
fp->bpf_func = (void *)ctx.target;
- fp->jited = 1;
+ fp->jited = true;
out:
kfree(ctx.offsets);
return;
diff --git a/arch/mips/net/bpf_jit.c b/arch/mips/net/bpf_jit.c
index cfa83cf2447dc..0e97ccd29fe3a 100644
--- a/arch/mips/net/bpf_jit.c
+++ b/arch/mips/net/bpf_jit.c
@@ -1417,7 +1417,7 @@ void bpf_jit_compile(struct bpf_prog *fp)
bpf_jit_dump(fp->len, alloc_size, 2, ctx.target);
fp->bpf_func = (void *)ctx.target;
- fp->jited = 1;
+ fp->jited = true;
out:
kfree(ctx.offsets);
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 40c53ff59124d..cbae2dfd053ca 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -686,7 +686,7 @@ void bpf_jit_compile(struct bpf_prog *fp)
((u64 *)image)[0] = (u64)code_base;
((u64 *)image)[1] = local_paca->kernel_toc;
fp->bpf_func = (void *)image;
- fp->jited = 1;
+ fp->jited = true;
}
out:
kfree(addrs);
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index b734f975c22e6..555f5c7e83abf 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -842,7 +842,7 @@ void bpf_jit_compile(struct bpf_prog *fp)
if (jit.start) {
set_memory_ro((unsigned long)header, header->pages);
fp->bpf_func = (void *) jit.start;
- fp->jited = 1;
+ fp->jited = true;
}
out:
kfree(addrs);
diff --git a/arch/sparc/net/bpf_jit_comp.c b/arch/sparc/net/bpf_jit_comp.c
index f7a736b645e84..b2ad9dc5425e2 100644
--- a/arch/sparc/net/bpf_jit_comp.c
+++ b/arch/sparc/net/bpf_jit_comp.c
@@ -801,7 +801,7 @@ cond_branch: f_offset = addrs[i + filter[i].jf];
if (image) {
bpf_flush_icache(image, image + proglen);
fp->bpf_func = (void *)image;
- fp->jited = 1;
+ fp->jited = true;
}
out:
kfree(addrs);
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 9de0b5476b0ca..d56cd1f515bdb 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -955,7 +955,7 @@ void bpf_int_jit_compile(struct bpf_prog *prog)
bpf_flush_icache(header, image + proglen);
set_memory_ro((unsigned long)header, header->pages);
prog->bpf_func = (void *)image;
- prog->jited = 1;
+ prog->jited = true;
}
out:
kfree(addrs);
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 868764fcffb84..4b59edead908c 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -300,9 +300,9 @@ struct bpf_work_struct {
};
struct bpf_prog {
- u32 pages; /* Number of allocated pages */
- u32 jited:1, /* Is our filter JIT'ed? */
- len:31; /* Number of filter blocks */
+ u16 pages; /* Number of allocated pages */
+ bool jited; /* Is our filter JIT'ed? */
+ u32 len; /* Number of filter blocks */
struct sock_fprog_kern *orig_prog; /* Original BPF program */
struct bpf_work_struct *work; /* Deferred free work struct */
unsigned int (*bpf_func)(const struct sk_buff *skb,
diff --git a/net/core/filter.c b/net/core/filter.c
index fa5b7d0f77acb..dfc716ffa44b3 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -972,7 +972,7 @@ static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp)
int err;
fp->bpf_func = NULL;
- fp->jited = 0;
+ fp->jited = false;
err = bpf_check_classic(fp->insns, fp->len);
if (err) {
--
2.30.2