bpf: fix net.core.bpf_jit_enable race
global bpf_jit_enable variable is tested multiple times in JITs,
blinding and verifier core. The malicious root can try to toggle
it while loading the programs. This race condition was accounted
for and there should be no issues, but it's safer to avoid
this race condition.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index c199990..4425189 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -1824,7 +1824,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
/* If BPF JIT was not enabled then we must fall back to
* the interpreter.
*/
- if (!bpf_jit_enable)
+ if (!prog->jit_requested)
return orig_prog;
/* If constant blinding was enabled and we failed during blinding
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index ba38d40..288137c 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -844,7 +844,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
int image_size;
u8 *image_ptr;
- if (!bpf_jit_enable)
+ if (!prog->jit_requested)
return orig_prog;
tmp = bpf_jit_blind_constants(prog);
diff --git a/arch/mips/net/ebpf_jit.c b/arch/mips/net/ebpf_jit.c
index 962b025..97069a1 100644
--- a/arch/mips/net/ebpf_jit.c
+++ b/arch/mips/net/ebpf_jit.c
@@ -1869,7 +1869,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
unsigned int image_size;
u8 *image_ptr;
- if (!bpf_jit_enable || !cpu_has_mips64r2)
+ if (!prog->jit_requested || !cpu_has_mips64r2)
return prog;
tmp = bpf_jit_blind_constants(prog);
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index 46d74e8..d5a5bc4 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -993,7 +993,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
struct bpf_prog *tmp_fp;
bool bpf_blinded = false;
- if (!bpf_jit_enable)
+ if (!fp->jit_requested)
return org_fp;
tmp_fp = bpf_jit_blind_constants(org_fp);
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index e81c168..f4baa8c 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -1300,7 +1300,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
struct bpf_jit jit;
int pass;
- if (!bpf_jit_enable)
+ if (!fp->jit_requested)
return orig_fp;
tmp = bpf_jit_blind_constants(fp);
diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c
index 5765e7e..a2f1b5e 100644
--- a/arch/sparc/net/bpf_jit_comp_64.c
+++ b/arch/sparc/net/bpf_jit_comp_64.c
@@ -1517,7 +1517,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
u8 *image_ptr;
int pass;
- if (!bpf_jit_enable)
+ if (!prog->jit_requested)
return orig_prog;
tmp = bpf_jit_blind_constants(prog);
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 0554e8a..68859b5 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1121,7 +1121,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
int pass;
int i;
- if (!bpf_jit_enable)
+ if (!prog->jit_requested)
return orig_prog;
tmp = bpf_jit_blind_constants(prog);