[gold commit] PR gold/14860: Fix race condition.
Cary Coutant
ccoutant@google.com
Thu Nov 14 18:45:00 GMT 2013
This patch fixes a race condition in Eh_frame_hdr::record_fde. When
running multi-threaded, many Write_sections tasks may call record_fde_,
which pushes an entry onto a shared vector. We need to hold a lock
while modifying the vector.
-cary
2013-11-14 Cary Coutant <ccoutant@google.com>
gold/
PR gold/14860
* ehframe.cc (Eh_frame_hdr::Eh_frame_hdr): Initialize lock_.
(Ehframe_hdr::set_final_data_size): Allocate a Lock.
* ehframe.h (Eh_frame_hdr::record_fde): Hold the lock while
updating fde_offsets_.
(Eh_frame_hdr::lock_): New data member.
commit b8b27651e665a28de137c1dcfca501b41424788d
Author: Cary Coutant <ccoutant@google.com>
Date: Fri Oct 11 14:12:16 2013 -0700
Fix race condition in Eh_frame_hdr.
diff --git a/gold/ehframe.cc b/gold/ehframe.cc
index 08a9ec6..be262bf 100644
--- a/gold/ehframe.cc
+++ b/gold/ehframe.cc
@@ -84,7 +84,8 @@ Eh_frame_hdr::Eh_frame_hdr(Output_section* eh_frame_section,
eh_frame_section_(eh_frame_section),
eh_frame_data_(eh_frame_data),
fde_offsets_(),
- any_unrecognized_eh_frame_sections_(false)
+ any_unrecognized_eh_frame_sections_(false),
+ lock_(NULL)
{
}
@@ -102,6 +103,9 @@ Eh_frame_hdr::set_final_data_size()
this->fde_offsets_.reserve(fde_count);
}
this->set_data_size(data_size);
+ // We need a lock for updating the fde_offsets_ vector while writing
+ // the FDEs.
+ this->lock_ = new Lock();
}
// Write the data to the file.
diff --git a/gold/ehframe.h b/gold/ehframe.h
index 8aab8b8..d5ac668 100644
--- a/gold/ehframe.h
+++ b/gold/ehframe.h
@@ -60,7 +60,10 @@ class Eh_frame_hdr : public Output_section_data
record_fde(section_offset_type fde_offset, unsigned char fde_encoding)
{
if (!this->any_unrecognized_eh_frame_sections_)
- this->fde_offsets_.push_back(std::make_pair(fde_offset, fde_encoding));
+ {
+ Hold_lock(*this->lock_);
+ this->fde_offsets_.push_back(std::make_pair(fde_offset, fde_encoding));
+ }
}
protected:
@@ -157,6 +160,8 @@ class Eh_frame_hdr : public Output_section_data
// Whether we found any .eh_frame sections which we could not
// process.
bool any_unrecognized_eh_frame_sections_;
+ // Lock held while updating fde_offsets_.
+ Lock* lock_;
};
// This class holds an FDE.
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