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| author | David S. Miller <davem@davemloft.net> | 2018-10-06 14:43:42 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-10-06 14:43:42 -0700 |
| commit | 72438f8cef4e75a22140853baa4c68392c721b22 (patch) | |
| tree | 78b7b6dafd827e0d55150a227db3978d91c0b6dd /kernel/bpf/verifier.c | |
| parent | fb4ee67529ff3e4c5874768477887c2df5714c96 (diff) | |
| parent | c1d84a1b42ef70d8ae601df9cadedc7ed4f1beb1 (diff) | |
| download | linux-72438f8cef4e75a22140853baa4c68392c721b22.tar.gz | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Diffstat (limited to 'kernel/bpf/verifier.c')
| -rw-r--r-- | kernel/bpf/verifier.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index e986518d7bc3..3584ab27d25c 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2842,6 +2842,15 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env, u64 umin_val, umax_val; u64 insn_bitness = (BPF_CLASS(insn->code) == BPF_ALU64) ? 64 : 32; + if (insn_bitness == 32) { + /* Relevant for 32-bit RSH: Information can propagate towards + * LSB, so it isn't sufficient to only truncate the output to + * 32 bits. + */ + coerce_reg_to_size(dst_reg, 4); + coerce_reg_to_size(&src_reg, 4); + } + smin_val = src_reg.smin_value; smax_val = src_reg.smax_value; umin_val = src_reg.umin_value; @@ -3077,7 +3086,6 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env, if (BPF_CLASS(insn->code) != BPF_ALU64) { /* 32-bit ALU ops are (32,32)->32 */ coerce_reg_to_size(dst_reg, 4); - coerce_reg_to_size(&src_reg, 4); } __reg_deduce_bounds(dst_reg); |