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authorDavid S. Miller <davem@davemloft.net>2017-08-01 10:07:50 -0700
committerDavid S. Miller <davem@davemloft.net>2017-08-01 10:07:50 -0700
commit29fda25a2d31098044f8dfa177c4d2834071828e (patch)
tree9e4be11c49a4405c19ece8f81fbb1db478da1055 /kernel/bpf/verifier.c
parentbb1182bc3e5956a93ab3ef8a3cbfb7966c42a94a (diff)
parentbc78d646e708dabd1744ca98744dea316f459497 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two minor conflicts in virtio_net driver (bug fix overlapping addition of a helper) and MAINTAINERS (new driver edit overlapping revamp of PHY entry). Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel/bpf/verifier.c')
-rw-r--r--kernel/bpf/verifier.c21
1 files changed, 15 insertions, 6 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index db6a289ebf0b..f6e8b3887eab 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1877,10 +1877,12 @@ static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
* do our normal operations to the register, we need to set the values
* to the min/max since they are undefined.
*/
- if (min_val == BPF_REGISTER_MIN_RANGE)
- dst_reg->min_value = BPF_REGISTER_MIN_RANGE;
- if (max_val == BPF_REGISTER_MAX_RANGE)
- dst_reg->max_value = BPF_REGISTER_MAX_RANGE;
+ if (opcode != BPF_SUB) {
+ if (min_val == BPF_REGISTER_MIN_RANGE)
+ dst_reg->min_value = BPF_REGISTER_MIN_RANGE;
+ if (max_val == BPF_REGISTER_MAX_RANGE)
+ dst_reg->max_value = BPF_REGISTER_MAX_RANGE;
+ }
switch (opcode) {
case BPF_ADD:
@@ -1891,10 +1893,17 @@ static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
dst_reg->min_align = min(src_align, dst_align);
break;
case BPF_SUB:
+ /* If one of our values was at the end of our ranges, then the
+ * _opposite_ value in the dst_reg goes to the end of our range.
+ */
+ if (min_val == BPF_REGISTER_MIN_RANGE)
+ dst_reg->max_value = BPF_REGISTER_MAX_RANGE;
+ if (max_val == BPF_REGISTER_MAX_RANGE)
+ dst_reg->min_value = BPF_REGISTER_MIN_RANGE;
if (dst_reg->min_value != BPF_REGISTER_MIN_RANGE)
- dst_reg->min_value -= min_val;
+ dst_reg->min_value -= max_val;
if (dst_reg->max_value != BPF_REGISTER_MAX_RANGE)
- dst_reg->max_value -= max_val;
+ dst_reg->max_value -= min_val;
dst_reg->min_align = min(src_align, dst_align);
break;
case BPF_MUL: