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* Fixed checks for exceeding limit of locals space. Prevent range and overflow errors during the checks. Introduced the MaxLocalsSize constant which provides the maximum possible size of locals space (stack frame) depending of bitness of a cpu.

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git-svn-id: trunk@39916 -
This commit is contained in:
yury 2018-10-12 14:43:17 +00:00
parent 4860f3934a
commit d0b6f427d3
2 changed files with 23 additions and 9 deletions
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8
compiler/globtype.pas
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@ -87,6 +87,14 @@ interface
AIntBits = 8;
{$endif cpu8bitalu}
{ Maximum possible size of locals space (stack frame) }
Const
{$if defined(cpu8bitalu) or defined(cpu16bitalu)}
MaxLocalsSize = High(AWord);
{$else}
MaxLocalsSize = High(longint) - 15;
{$endif}
Type
PAWord = ^AWord;
PAInt = ^AInt;

24
compiler/tgobj.pas
View File

@ -274,6 +274,11 @@ implementation
freetype:=Used2Free[temptype];
if freetype=tt_none then
internalerror(200208201);
if size>MaxLocalsSize then
begin
CGMessage(cg_e_localsize_too_big);
size:=0; // Prevent further range check errors
end;
size:=align(size,alignment);
{ First check the tmpfreelist, but not when
we don't want to reuse an already allocated block }
@ -417,29 +422,30 @@ implementation
tl^.temptype:=temptype;
tl^.def:=def;
{$push}
{$r-}
{$warn 6018 off}
{$warn 4044 off}
{ Extend the temp }
if direction=-1 then
begin
if qword(align(-lasttemp-alignmismatch,alignment))+size+alignmismatch>high(tl^.pos) then
CGMessage(cg_e_localsize_too_big);
if qword(align(-lasttemp-alignmismatch,alignment))+size+alignmismatch>MaxLocalsSize then
begin
CGMessage(cg_e_localsize_too_big);
size:=0; // Prevent further range check errors
end;
lasttemp:=(-align(-lasttemp-alignmismatch,alignment))-size-alignmismatch;
tl^.pos:=lasttemp;
end
else
begin
tl^.pos:=align(lasttemp+alignmismatch,alignment)-alignmismatch;
if qword(tl^.pos)+size>high(tl^.pos) then
CGMessage(cg_e_localsize_too_big);
if qword(tl^.pos)+size>MaxLocalsSize then
begin
CGMessage(cg_e_localsize_too_big);
size:=0; // Prevent further range check errors
end;
lasttemp:=tl^.pos+size;
end;
{$ifdef EXTDEBUG}
Comment(V_Note,'tgobj: (AllocTemp) lasttemp set to '+tostr(lasttemp));
{$endif}
{$pop}
tl^.fini:=fini;
tl^.alignment:=alignment;
tl^.size:=size;