paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-04-08 01:08:07 +02:00
Code Issues Packages Projects Releases Wiki Activity

* Check buffer overflow when reading

Browse Source 
git-svn-id: trunk@49012 -
This commit is contained in:
michael 2021-03-19 14:25:21 +00:00
parent 28e359f091
commit 2a96ad2715
1 changed files with 8 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
rtl/unix/timezone.inc
View File

@ -278,6 +278,7 @@ var
buf : array[0..bufsize-1] of byte;
bufptr : pbyte;
bufbytes : tsSize;
bufoverflow : boolean;
f : longint;
tzhead : ttzhead;
@ -288,22 +289,22 @@ var
readfilebuf:=bufbytes;
end;
Procedure checkbufptr;
Procedure checkbufptr(asize : integer);
var
a : tssize;
begin
a:=bufptr-@buf;
a:=bufptr-@buf+asize;
if (a>bufbytes) then
Writeln('Reading past end of file : ',a);
bufoverflow:=true;
end;
function readbufbyte: byte;
begin
// checkbufptr;
if bufptr > @buf[bufsize-1] then
readfilebuf;
checkbufptr(1);
readbufbyte := bufptr^;
inc(bufptr);
end;
@ -319,13 +320,13 @@ var
numbytes := count;
if numbytes > 0 then
begin
checkbufptr(numbytes);
if assigned(dest) then
move(bufptr^, dest^, numbytes);
inc(bufptr, numbytes);
dec(count, numbytes);
inc(readbuf, numbytes);
inc(dest, numbytes);
// checkbufptr;
end;
if count > 0 then
readfilebuf
@ -462,10 +463,11 @@ begin
f:=fpopen(fn,Open_RdOnly);
if f<0 then
exit(False);
bufoverflow:=false;
bufptr := @buf[bufsize-1]+1;
tzhead:=default(ttzhead);
LockTZInfo;
ReadTimezoneFile:=(readheader() and readdata());
ReadTimezoneFile:=(readheader() and readdata()) and not BufOverflow;
ClearCurrentTZinfo;
UnlockTZInfo;
fpclose(f);