| Message ID | c9ab0efb-d401-c42c-4bd2-e848ebef0c87@suse.cz |
|---|---|
| State | New |
| Headers | show |
PING^1 On 06/13/2017 10:09 AM, Martin Liška wrote: > Hi. > > For a function that does not handle an expection (and calls BUILT_IN_UNWIND_RESUME), > we need to emit call to BUILT_IN_ASAN_HANDLE_NO_RETURN. That will clean up stack > which can possibly contain poisoned shadow memory that will not be cleaned-up > in function prologue. > > Patch can bootstrap on ppc64le-redhat-linux and survives regression tests. > > Ready to be installed? > Martin > > gcc/testsuite/ChangeLog: > > 2017-06-12 Martin Liska <mliska@suse.cz> > > PR sanitizer/81021 > * g++.dg/asan/pr81021.C: New test. > > gcc/ChangeLog: > > 2017-06-12 Martin Liska <mliska@suse.cz> > > PR sanitizer/81021 > * tree-eh.c (lower_resx): Call BUILT_IN_ASAN_HANDLE_NO_RETURN > before BUILT_IN_UNWIND_RESUME when ASAN is used. > --- > gcc/testsuite/g++.dg/asan/pr81021.C | 33 +++++++++++++++++++++++++++++++++ > gcc/tree-eh.c | 14 ++++++++++++++ > 2 files changed, 47 insertions(+) > create mode 100644 gcc/testsuite/g++.dg/asan/pr81021.C > >
PING^2 On 06/20/2017 02:15 PM, Martin Liška wrote: > PING^1 > > On 06/13/2017 10:09 AM, Martin Liška wrote: >> Hi. >> >> For a function that does not handle an expection (and calls BUILT_IN_UNWIND_RESUME), >> we need to emit call to BUILT_IN_ASAN_HANDLE_NO_RETURN. That will clean up stack >> which can possibly contain poisoned shadow memory that will not be cleaned-up >> in function prologue. >> >> Patch can bootstrap on ppc64le-redhat-linux and survives regression tests. >> >> Ready to be installed? >> Martin >> >> gcc/testsuite/ChangeLog: >> >> 2017-06-12 Martin Liska <mliska@suse.cz> >> >> PR sanitizer/81021 >> * g++.dg/asan/pr81021.C: New test. >> >> gcc/ChangeLog: >> >> 2017-06-12 Martin Liska <mliska@suse.cz> >> >> PR sanitizer/81021 >> * tree-eh.c (lower_resx): Call BUILT_IN_ASAN_HANDLE_NO_RETURN >> before BUILT_IN_UNWIND_RESUME when ASAN is used. >> --- >> gcc/testsuite/g++.dg/asan/pr81021.C | 33 +++++++++++++++++++++++++++++++++ >> gcc/tree-eh.c | 14 ++++++++++++++ >> 2 files changed, 47 insertions(+) >> create mode 100644 gcc/testsuite/g++.dg/asan/pr81021.C >> >> >
On 06/13/2017 02:09 AM, Martin Liška wrote: > Hi. > > For a function that does not handle an expection (and calls BUILT_IN_UNWIND_RESUME), > we need to emit call to BUILT_IN_ASAN_HANDLE_NO_RETURN. That will clean up stack > which can possibly contain poisoned shadow memory that will not be cleaned-up > in function prologue. > > Patch can bootstrap on ppc64le-redhat-linux and survives regression tests. > > Ready to be installed? > Martin > > gcc/testsuite/ChangeLog: > > 2017-06-12 Martin Liska <mliska@suse.cz> > > PR sanitizer/81021 > * g++.dg/asan/pr81021.C: New test. > > gcc/ChangeLog: > > 2017-06-12 Martin Liska <mliska@suse.cz> > > PR sanitizer/81021 > * tree-eh.c (lower_resx): Call BUILT_IN_ASAN_HANDLE_NO_RETURN > before BUILT_IN_UNWIND_RESUME when ASAN is used. OK. Jeff
diff --git a/gcc/testsuite/g++.dg/asan/pr81021.C b/gcc/testsuite/g++.dg/asan/pr81021.C new file mode 100644 index 00000000000..daa0525c273 --- /dev/null +++ b/gcc/testsuite/g++.dg/asan/pr81021.C @@ -0,0 +1,33 @@ +// { dg-do run } + +#include <string> + +struct ConfigFile { + ConfigFile(std::string filename, std::string delimiter) { throw "error"; } + ConfigFile(std::string filename) {} +}; + +struct Configuration { + ConfigFile _configFile; + + Configuration(const std::string &root, const char *baseName) + : _configFile(root + baseName, "=") { } + Configuration(const std::string &root, const char *a, const char *b) + : _configFile(root + a + b) { } +}; + + +void test() { + std::string root("etc"); + try { + Configuration config(root, "notthere"); + } + catch (...) { + // exception is thrown, caught here and ignored... + } + Configuration config(root, "a", "b"); // ASAN error during constructor here +} + +int main(int argc, const char *argv[]) { + test(); +} diff --git a/gcc/tree-eh.c b/gcc/tree-eh.c index fc016d795b7..fdd348c52e9 100644 --- a/gcc/tree-eh.c +++ b/gcc/tree-eh.c @@ -3304,6 +3304,20 @@ lower_resx (basic_block bb, gresx *stmt, gimple_call_set_lhs (x, var); gsi_insert_before (&gsi, x, GSI_SAME_STMT); + /* When exception handling is delegated to a caller function, we + have to guarantee that shadow memory variables living on stack + will be cleaner before control is given to a parent function. */ + if ((flag_sanitize & SANITIZE_ADDRESS) != 0 + && !lookup_attribute ("no_sanitize_address", + DECL_ATTRIBUTES (current_function_decl))) + { + tree decl + = builtin_decl_implicit (BUILT_IN_ASAN_HANDLE_NO_RETURN); + gimple *g = gimple_build_call (decl, 0); + gimple_set_location (g, gimple_location (stmt)); + gsi_insert_before (&gsi, g, GSI_SAME_STMT); + } + fn = builtin_decl_implicit (BUILT_IN_UNWIND_RESUME); x = gimple_build_call (fn, 1, var); gsi_insert_before (&gsi, x, GSI_SAME_STMT);