[PATCH] bpf: remove unnecessary condition in bpf_check()

From: Tobias Tefke
Date: Mon Jul 09 2018 - 07:49:33 EST


In the label skip_full_check the function sanitize_dead_code()
is being called if the return value equals zero.
After that call there is another condition checking
if the return value equals zero.
If this condition evaluates to true,
check_max_stack_depth() is being called.
However, sanitize_dead_code() has no return value.
Therefore the return value of bpf_check() is still the same
and the condition can be removed.

Signed-off-by: Tobias Tefke <tobias.tefke@xxxxxxxxxxxx>
---
kernel/bpf/verifier.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 9e2bf834f13a..b022d0a85427 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5935,11 +5935,10 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
while (!pop_stack(env, NULL, NULL));
free_states(env);

- if (ret == 0)
+ if (ret == 0) {
sanitize_dead_code(env);
-
- if (ret == 0)
ret = check_max_stack_depth(env);
+ }

if (ret == 0)
/* program is valid, convert *(u32*)(ctx + off) accesses */
--
2.18.0