Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Alexei Starovoitov says:

====================
pull-request: bpf 2020-12-10

The following pull-request contains BPF updates for your *net* tree.

We've added 21 non-merge commits during the last 12 day(s) which contain
a total of 21 files changed, 163 insertions(+), 88 deletions(-).

The main changes are:

1) Fix propagation of 32-bit signed bounds from 64-bit bounds, from Alexei.

2) Fix ring_buffer__poll() return value, from Andrii.

3) Fix race in lwt_bpf, from Cong.

4) Fix test_offload, from Toke.

5) Various xsk fixes.

Please consider pulling these changes from:

  git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git

Thanks a lot!

Also thanks to reporters, reviewers and testers of commits in this pull-request:

Cong Wang, Hulk Robot, Jakub Kicinski, Jean-Philippe Brucker, John
Fastabend, Magnus Karlsson, Maxim Mikityanskiy, Yonghong Song
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 5 deletions

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 1388bf733071..53fe6ef6d931 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1298,9 +1298,7 @@ static void __reg_combine_32_into_64(struct bpf_reg_state *reg)
 
 static bool __reg64_bound_s32(s64 a)
 {
-	if (a > S32_MIN && a < S32_MAX)
-		return true;
-	return false;
+	return a > S32_MIN && a < S32_MAX;
 }
 
 static bool __reg64_bound_u32(u64 a)
@@ -1314,10 +1312,10 @@ static void __reg_combine_64_into_32(struct bpf_reg_state *reg)
 {
 	__mark_reg32_unbounded(reg);
 
-	if (__reg64_bound_s32(reg->smin_value))
+	if (__reg64_bound_s32(reg->smin_value) && __reg64_bound_s32(reg->smax_value)) {
 		reg->s32_min_value = (s32)reg->smin_value;
-	if (__reg64_bound_s32(reg->smax_value))
 		reg->s32_max_value = (s32)reg->smax_value;
+	}
 	if (__reg64_bound_u32(reg->umin_value))
 		reg->u32_min_value = (u32)reg->umin_value;
 	if (__reg64_bound_u32(reg->umax_value))
@@ -4895,6 +4893,8 @@ static void do_refine_retval_range(struct bpf_reg_state *regs, int ret_type,
 
 	ret_reg->smax_value = meta->msize_max_value;
 	ret_reg->s32_max_value = meta->msize_max_value;
+	ret_reg->smin_value = -MAX_ERRNO;
+	ret_reg->s32_min_value = -MAX_ERRNO;
 	__reg_deduce_bounds(ret_reg);
 	__reg_bound_offset(ret_reg);
 	__update_reg_bounds(ret_reg);