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Differential D63906

hwasan: Fix an off-by-one error in PrintTagsAroundAddr.
ClosedPublic

Authored by pcc on Jun 27 2019, 4:21 PM.

Details

Reviewers
eugenis
Commits
rG559b2e0187a1: hwasan: Fix an off-by-one error in PrintTagsAroundAddr.
rCRT364609: hwasan: Fix an off-by-one error in PrintTagsAroundAddr.
rL364609: hwasan: Fix an off-by-one error in PrintTagsAroundAddr.
Summary

Previously we were printing 16 rows of tags, not 17.

Diff Detail

Event Timeline

pcc created this revision.Jun 27 2019, 4:21 PM
Herald added projects: Restricted Project, Restricted Project. · View Herald TranscriptJun 27 2019, 4:21 PM
Herald added subscribers: Restricted Project, kubamracek. · View Herald Transcript
Harbormaster completed remote builds in B34035: Diff 206961.Jun 27 2019, 4:22 PM
eugenis accepted this revision.Jun 27 2019, 4:23 PM

LGTM

This revision is now accepted and ready to land.Jun 27 2019, 4:23 PM
Closed by commit rL364609: hwasan: Fix an off-by-one error in PrintTagsAroundAddr. (authored by pcc). · Explain WhyJun 27 2019, 4:29 PM
This revision was automatically updated to reflect the committed changes.
Herald added a subscriber: delcypher. · View Herald TranscriptJun 27 2019, 4:29 PM

Revision Contents

PathSize
compiler-rt/
lib/
hwasan/
2 lines

Diff 206961

compiler-rt/lib/hwasan/hwasan_report.cpp

Show First 20 Lines • Show All 283 Lines • ▼ Show 20 Lines Printf(
"Memory tags around the buggy address (one tag corresponds to %zd " "Memory tags around the buggy address (one tag corresponds to %zd "
"bytes):\n", kShadowAlignment); "bytes):\n", kShadowAlignment);
const uptr row_len = 16; // better be power of two. const uptr row_len = 16; // better be power of two.
const uptr num_rows = 17; const uptr num_rows = 17;
tag_t *center_row_beg = reinterpret_cast<tag_t *>( tag_t *center_row_beg = reinterpret_cast<tag_t *>(
RoundDownTo(reinterpret_cast<uptr>(tag_ptr), row_len)); RoundDownTo(reinterpret_cast<uptr>(tag_ptr), row_len));
tag_t *beg_row = center_row_beg - row_len * (num_rows / 2); tag_t *beg_row = center_row_beg - row_len * (num_rows / 2);
tag_t *end_row = center_row_beg + row_len * (num_rows / 2); tag_t *end_row = center_row_beg + row_len * ((num_rows + 1) / 2);
InternalScopedString s(GetPageSizeCached() * 8); InternalScopedString s(GetPageSizeCached() * 8);
for (tag_t *row = beg_row; row < end_row; row += row_len) { for (tag_t *row = beg_row; row < end_row; row += row_len) {
s.append("%s", row == center_row_beg ? "=>" : " "); s.append("%s", row == center_row_beg ? "=>" : " ");
for (uptr i = 0; i < row_len; i++) { for (uptr i = 0; i < row_len; i++) {
s.append("%s", row + i == tag_ptr ? "[" : " "); s.append("%s", row + i == tag_ptr ? "[" : " ");
s.append("%02x", row[i]); s.append("%02x", row[i]);
s.append("%s", row + i == tag_ptr ? "]" : " "); s.append("%s", row + i == tag_ptr ? "]" : " ");
} }
▲ Show 20 Lines • Show All 167 Lines • Show Last 20 Lines