Your message dated Fri, 3 Oct 2008 20:26:44 +0100
with message-id <[EMAIL PROTECTED]>
and subject line spim has been removed from Debian, closing #182827
has caused the Debian Bug report #182827,
regarding spim: syscall read_string is broken by design
to be marked as done.
This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.
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--
182827: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=182827
Debian Bug Tracking System
Contact [EMAIL PROTECTED] with problems
--- Begin Message ---
Package: spim
Version: 6.5-1
Severity: important
The semantics of read_string is badly broken, as is that of read_char:
there is no means to know when EOF is met. It seems that the author
means \0 to stand for EOF, which is not satisfying. But worse yet:
the intend semantics is not implemented properly, which results in the
following incorrect behavior:
~/src/spim % cat spim-bug-report.s nostromo 8:36
.data
getchbuf:
.space 200
.text
main:
la $a0, getchbuf
li $a1, 200
li $v0, 8
syscall
la $a0, getchbuf
li $v0, 4
syscall
li $v0, 10
syscall
~/src/spim % echo -n foo | spim -file spim-bug-report.s nostromo 8:37
SPIM Version 6.5 of January 4, 2003
Copyright 1990-2003 by James R. Larus ([EMAIL PROTECTED]).
All Rights Reserved.
See the file README for a full copyright notice.
Loaded: /usr/lib/spim/trap.handler
fooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
Pay special attention to the -n in the echo command. The problem
exhibits itself more easily this way, but even inputs with \n in it
are vulnerable.
I suggest the following patch, which does fix the issue:
~/src/spim % diff spim.c~ spim.c -u nostromo Err 1
--- spim.c~ 1999-01-08 01:33:34.000000000 +0100
+++ spim.c 2003-02-28 08:32:02.000000000 +0100
@@ -1,7 +1,7 @@
/* SPIM S20 MIPS simulator.
Terminal interface for SPIM simulator.
- Copyright (C) 1990-1998 by James Larus ([EMAIL PROTECTED]).
+ Copyright (C) 1990-1998, 2003 by James Larus ([EMAIL PROTECTED]).
ALL RIGHTS RESERVED.
Changes for DOS and Windows versions by David A. Carley ([EMAIL PROTECTED])
@@ -927,7 +927,10 @@
while (1 < str_size) /* Reserve space for null */
{
char buf[1];
- read ((int) console_in.i, buf, 1); /* Not in raw mode! */
+
+ /* Not in raw mode! */
+ if (!read ((int) console_in.i, buf, 1))
+ break;
*ptr ++ = buf[0];
str_size -= 1;
But if I can make a suggestion, I would vote for read_string to return
in $a0 the number of characters read. It corresponds to the following
longer patch:
------------------------------
--- spim.c.orig 2003-02-28 08:41:12.000000000 +0100
+++ spim.c 2003-02-28 08:41:59.000000000 +0100
@@ -1,7 +1,7 @@
/* SPIM S20 MIPS simulator.
Terminal interface for SPIM simulator.
- Copyright (C) 1990-1998 by James Larus ([EMAIL PROTECTED]).
+ Copyright (C) 1990-1998, 2003 by James Larus ([EMAIL PROTECTED]).
ALL RIGHTS RESERVED.
Changes for DOS and Windows versions by David A. Carley ([EMAIL PROTECTED])
@@ -904,10 +904,10 @@
/* Simulate the semantics of fgets (not gets) on Unix file. */
#ifdef __STDC__
-void
+int
read_input (char *str, int str_size)
#else
-void
+int
read_input (str, str_size)
char *str;
int str_size;
@@ -927,7 +927,10 @@
while (1 < str_size) /* Reserve space for null */
{
char buf[1];
- read ((int) console_in.i, buf, 1); /* Not in raw mode! */
+
+ /* Not in raw mode! */
+ if (!read ((int) console_in.i, buf, 1))
+ break;
*ptr ++ = buf[0];
str_size -= 1;
@@ -941,6 +944,8 @@
if (restore_console_to_program)
console_to_program ();
+
+ return ptr - str;
}
--- spim.h.orig 2003-02-28 08:41:21.000000000 +0100
+++ spim.h 2003-02-28 08:42:14.000000000 +0100
@@ -1,7 +1,7 @@
/* SPIM S20 MIPS simulator.
Definitions for the SPIM S20.
- Copyright (C) 1990-1998 by James Larus ([EMAIL PROTECTED]).
+ Copyright (C) 1990-1998, 2003 by James Larus ([EMAIL PROTECTED]).
ALL RIGHTS RESERVED.
Changes for DOS and Windows versions by David A. Carley ([EMAIL PROTECTED])
@@ -231,7 +231,7 @@
void fatal_error (char *fmt, ...);
char get_console_char (void);
void put_console_char (char c);
-void read_input (char *str, int n);
+int read_input (char *str, int n);
int* run_error (char *fmt, ...);
void write_output (port, char *fmt, ...);
#else
--- mips-syscall.c.orig 2003-02-28 08:43:39.000000000 +0100
+++ mips-syscall.c 2003-02-28 08:44:06.000000000 +0100
@@ -2,7 +2,7 @@
Execute SPIM syscalls, both in simulator and bare mode.
Execute MIPS syscalls in bare mode, when running on MIPS systems.
- Copyright (C) 1990-1998 by James Larus ([EMAIL PROTECTED]).
+ Copyright (C) 1990-1998, 2003 by James Larus ([EMAIL PROTECTED]).
ALL RIGHTS RESERVED.
Improved by Emin Gun Sirer.
@@ -458,7 +458,8 @@
case READ_STRING_SYSCALL:
{
- read_input ( (char *) MEM_ADDRESS (R[REG_A0]), R[REG_A1]);
+ R[REG_RES] =
+ read_input ( (char *) MEM_ADDRESS (R[REG_A0]), R[REG_A1]);
data_modified = 1;
break;
}
------------------------------
Which behaves like properly, according to the following test case:
------------------------------
~/src/spim % cat spim-bug-report.s nostromo 8:46
.data
getchbuf:
.space 200
.text
main:
la $a0, getchbuf
li $a1, 200
li $v0, 8
syscall
move $a0, $v0
li $v0, 1
syscall
la $a0, getchbuf
li $v0, 4
syscall
li $v0, 10
syscall
~/src/spim % echo -n foo | ./spim -file spim-bug-report.s; echo nostromo 8:48
SPIM Version 6.2 of January 11, 1999
Copyright 1990-1998 by James R. Larus ([EMAIL PROTECTED]).
All Rights Reserved.
See the file README for a full copyright notice.
Loaded: /usr/local/share/spim/trap.handler
3foo
------------------------------
Of course, the documentation will have to be updated.
PS/ '\0' should definitely not be EOF :(
-- System Information
Debian Release: testing/unstable
Kernel Version: Linux nostromo 2.4.20 #4 jeu fév 27 14:06:02 CET 2003 i686
unknown unknown GNU/Linux
Versions of the packages spim depends on:
ii libc6 2.3.1-13 GNU C Library: Shared libraries and Timezone
ii libxaw7 4.2.1-5 X Athena widget set library
ii xlibs 4.2.1-5 X Window System client libraries
--- End Message ---
--- Begin Message ---
Version: 7.3-1+rm
The spim package has been removed from Debian testing, unstable and
experimental, so I am now closing the bugs that were still opened
against it.
For more information about this package's removal, read
http://bugs.debian.org/354501 . That bug might give the reasons why
this package was removed, and suggestions of possible replacements.
Don't hesitate to reply to this mail if you have any question.
Thank you for your contribution to Debian.
--
Marco Rodrigues
http://Marco.Tondela.org
--- End Message ---
