Package: coreutils;
Reported by: Jim Meyering <jim <at> meyering.net>
Date: Sun, 2 Jun 2013 02:42:01 UTC
Severity: normal
Tags: fixed, patch
Done: Assaf Gordon <assafgordon <at> gmail.com>
Bug is archived. No further changes may be made.
Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):
From: Jim Meyering <jim <at> meyering.net> To: bug-coreutils <at> gnu.org Cc: Rich Burridge <rich.burridge <at> oracle.com> Subject: [PATCH] od: -wN, N>64K, avoid misbehavior on systems with 32-bit size_t Date: Sun, 02 Jun 2013 04:39:24 +0200
Rich reported this bug privately.
Here's a proposed patch.
I could have fixed the underlying problem with
explicit casts to a wider type (including floating point types),
but this seemed cleanest, if perhaps a little too subtle.
I'd rather not write a comment in each of three places,
and didn't really want to factor out a 3-input function
just to compute each next_pad value.
Along the way, I noticed that an unreasonably large width
caused trouble, but I'm not inclined to worry about it:
$ : | od -An -a -w$(echo 2^32-1|bc)
od: memory exhausted
From 19a4227793820f74bd6ca503ded3fafe65425eff Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyering <at> fb.com>
Date: Sat, 1 Jun 2013 19:20:06 -0700
Subject: [PATCH] od: -wN, N>64K, avoid misbehavior on systems with 32-bit
size_t
* src/od.c (PRINT_FIELDS): Declare "i" to be of type uintmax_t, so that
the numerator in the expression for "next_pad" does not overflow.
(print_named_ascii): Likewise.
(print_ascii): Likewise.
Bug introduced via commit v6.12-42-g20c0b87.
* tests/misc/od.pl: Exercise each of the three affected code paths.
* NEWS (Bug fixes): Mention it.
Reported by Rich Burridge.
---
NEWS | 4 ++++
THANKS.in | 1 +
src/od.c | 6 +++---
tests/misc/od.pl | 7 +++++++
4 files changed, 15 insertions(+), 3 deletions(-)
diff --git a/NEWS b/NEWS
index 721e05b..cad5eee 100644
--- a/NEWS
+++ b/NEWS
@@ -16,10 +16,14 @@ GNU coreutils NEWS -*- outline -*-
mkdir, mkfifo, and mknod now work better when creating a file in a directory
with a default ACL whose umask disagrees with the process's umask, on a
system such as GNU/Linux where directory ACL umasks override process umasks.
[bug introduced in coreutils-6.0]
+ od -wN with N larger than 64K on a system with 32-bit size_t would
+ print approximately 2*N bytes of extraneous padding.
+ [Bug introduced in coreutils-7.0]
+
tail --retry -f now waits for the files specified to appear. Before, tail
would immediately exit when such a file is inaccessible during the initial
open.
[This bug was introduced when inotify support was added in coreutils-7.5]
diff --git a/THANKS.in b/THANKS.in
index 67b60b9..f399d77 100644
--- a/THANKS.in
+++ b/THANKS.in
@@ -519,10 +519,11 @@ Rainer Orth ro <at> TechFak.Uni-Bielefeld.DE
Ralf W. Stephan stephan <at> tmt.de
Ralph Loader loader <at> maths.ox.ac.uk
Rasmus Borup Hansen rbh <at> intomics.com
Raul Miller moth <at> magenta.com
Raúl Núñez de Arenas Coronado raul <at> pleyades.net
+Rich Burridge rich.burridge <at> oracle.com
Richard A Downing richard.downing <at> bcs.org.uk
Richard Braakman dark <at> xs4all.nl
Richard Dawe rich <at> phekda.freeserve.co.uk
Richard J. Rauenzahn rrauenza <at> hairball.cup.hp.com
Richard Neill rn214 <at> hermes.cam.ac.uk
diff --git a/src/od.c b/src/od.c
index e8cab46..1c23401 100644
--- a/src/od.c
+++ b/src/od.c
@@ -398,11 +398,11 @@ and so on for G, T, P, E, Z, Y.\n\
static void \
N (size_t fields, size_t blank, void const *block, \
char const *FMT_STRING, int width, int pad) \
{ \
T const *p = block; \
- size_t i; \
+ uintmax_t i; \
int pad_remaining = pad; \
for (i = fields; blank < i; i--) \
{ \
int next_pad = pad * (i - 1) / fields; \
int adjusted_width = pad_remaining - next_pad + width; \
@@ -454,11 +454,11 @@ static void
print_named_ascii (size_t fields, size_t blank, void const *block,
const char *unused_fmt_string _GL_UNUSED,
int width, int pad)
{
unsigned char const *p = block;
- size_t i;
+ uintmax_t i;
int pad_remaining = pad;
for (i = fields; blank < i; i--)
{
int next_pad = pad * (i - 1) / fields;
int masked_c = *p++ & 0x7f;
@@ -485,11 +485,11 @@ static void
print_ascii (size_t fields, size_t blank, void const *block,
const char *unused_fmt_string _GL_UNUSED, int width,
int pad)
{
unsigned char const *p = block;
- size_t i;
+ uintmax_t i;
int pad_remaining = pad;
for (i = fields; blank < i; i--)
{
int next_pad = pad * (i - 1) / fields;
unsigned char c = *p++;
diff --git a/tests/misc/od.pl b/tests/misc/od.pl
index 0649b1c..fb579aa 100755
--- a/tests/misc/od.pl
+++ b/tests/misc/od.pl
@@ -55,10 +55,17 @@ my @Tests =
# Ensure that od -j doesn't fseek across a nonempty file in /proc,
# even if the kernel reports that the file has stat.st_size = 0.
['j-proc', "-An -c -j $proc_file_byte_count $proc_file",
{IN=>{f2=>'e'}}, {OUT=>" e\n"}],
+
+ # Ensure that a large width does not cause trouble.
+ # From coreutils-7.0 through coreutils-8.21, these would print
+ # approximately 128KiB of padding.
+ ['wide-a', '-a -w65537 -An', {IN=>{g=>'x'}}, {OUT=>" x\n"}],
+ ['wide-c', '-c -w65537 -An', {IN=>{g=>'x'}}, {OUT=>" x\n"}],
+ ['wide-x', '-tx1 -w65537 -An', {IN=>{g=>'B'}}, {OUT=>" 42\n"}],
);
my $save_temps = $ENV{DEBUG};
my $verbose = $ENV{VERBOSE};
--
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