Revision 5caaf5346892d1e7f0b8b7223062644f8538483f authored by Ian Munsie on 07 July 2015, 05:45:46 UTC, committed by Michael Ellerman on 08 July 2015, 05:17:46 UTC
This patch makes the mmap call fail outright if the requested region is larger than the problem state area assigned to the context so the error is reported immediately rather than waiting for an attempt to access an address out of bounds. Although we never expect users to map more than the assigned problem state area and are not aware of anyone doing this (other than for testing), this does have the potential to break users if someone has used a larger range regardless. I'm submitting it for consideration, but if this change is not considered acceptable the previous patch is sufficient to prevent access out of bounds without breaking anyone. Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
1 parent 3f8dc44
checkstack.pl
#!/usr/bin/perl
# Check the stack usage of functions
#
# Copyright Joern Engel <joern@lazybastard.org>
# Inspired by Linus Torvalds
# Original idea maybe from Keith Owens
# s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
# Mips port by Juan Quintela <quintela@mandrakesoft.com>
# IA64 port via Andreas Dilger
# Arm port by Holger Schurig
# sh64 port by Paul Mundt
# Random bits by Matt Mackall <mpm@selenic.com>
# M68k port by Geert Uytterhoeven and Andreas Schwab
# AVR32 port by Haavard Skinnemoen (Atmel)
# AArch64, PARISC ports by Kyle McMartin
# sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
#
# Usage:
# objdump -d vmlinux | scripts/checkstack.pl [arch]
#
# TODO : Port to all architectures (one regex per arch)
use strict;
# check for arch
#
# $re is used for two matches:
# $& (whole re) matches the complete objdump line with the stack growth
# $1 (first bracket) matches the size of the stack growth
#
# $dre is similar, but for dynamic stack redutions:
# $& (whole re) matches the complete objdump line with the stack growth
# $1 (first bracket) matches the dynamic amount of the stack growth
#
# use anything else and feel the pain ;)
my (@stack, $re, $dre, $x, $xs, $funcre);
{
my $arch = shift;
if ($arch eq "") {
$arch = `uname -m`;
chomp($arch);
}
$x = "[0-9a-f]"; # hex character
$xs = "[0-9a-f ]"; # hex character or space
$funcre = qr/^$x* <(.*)>:$/;
if ($arch eq 'aarch64') {
#ffffffc0006325cc: a9bb7bfd stp x29, x30, [sp,#-80]!
$re = qr/^.*stp.*sp,\#-([0-9]{1,8})\]\!/o;
} elsif ($arch eq 'arm') {
#c0008ffc: e24dd064 sub sp, sp, #100 ; 0x64
$re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
} elsif ($arch eq 'avr32') {
#8000008a: 20 1d sub sp,4
#80000ca8: fa cd 05 b0 sub sp,sp,1456
$re = qr/^.*sub.*sp.*,([0-9]{1,8})/o;
} elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
#c0105234: 81 ec ac 05 00 00 sub $0x5ac,%esp
# or
# 2f60: 48 81 ec e8 05 00 00 sub $0x5e8,%rsp
$re = qr/^.*[as][du][db] \$(0x$x{1,8}),\%(e|r)sp$/o;
$dre = qr/^.*[as][du][db] (%.*),\%(e|r)sp$/o;
} elsif ($arch eq 'ia64') {
#e0000000044011fc: 01 0f fc 8c adds r12=-384,r12
$re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
} elsif ($arch eq 'm68k') {
# 2b6c: 4e56 fb70 linkw %fp,#-1168
# 1df770: defc ffe4 addaw #-28,%sp
$re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
} elsif ($arch eq 'metag') {
#400026fc: 40 00 00 82 ADD A0StP,A0StP,#0x8
$re = qr/.*ADD.*A0StP,A0StP,\#(0x$x{1,8})/o;
$funcre = qr/^$x* <[^\$](.*)>:$/;
} elsif ($arch eq 'mips64') {
#8800402c: 67bdfff0 daddiu sp,sp,-16
$re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
} elsif ($arch eq 'mips') {
#88003254: 27bdffe0 addiu sp,sp,-32
$re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
} elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
$re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
} elsif ($arch eq 'ppc') {
#c00029f4: 94 21 ff 30 stwu r1,-208(r1)
$re = qr/.*stwu.*r1,-($x{1,8})\(r1\)/o;
} elsif ($arch eq 'ppc64') {
#XXX
$re = qr/.*stdu.*r1,-($x{1,8})\(r1\)/o;
} elsif ($arch eq 'powerpc') {
$re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
} elsif ($arch =~ /^s390x?$/) {
# 11160: a7 fb ff 60 aghi %r15,-160
# or
# 100092: e3 f0 ff c8 ff 71 lay %r15,-56(%r15)
$re = qr/.*(?:lay|ag?hi).*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})
(?:\(\%r15\))?$/ox;
} elsif ($arch =~ /^sh64$/) {
#XXX: we only check for the immediate case presently,
# though we will want to check for the movi/sub
# pair for larger users. -- PFM.
#a00048e0: d4fc40f0 addi.l r15,-240,r15
$re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
} elsif ($arch =~ /^blackfin$/) {
# 0: 00 e8 38 01 LINK 0x4e0;
$re = qr/.*[[:space:]]LINK[[:space:]]*(0x$x{1,8})/o;
} elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
# f0019d10: 9d e3 bf 90 save %sp, -112, %sp
$re = qr/.*save.*%sp, -(([0-9]{2}|[3-9])[0-9]{2}), %sp/o;
} else {
print("wrong or unknown architecture \"$arch\"\n");
exit
}
}
#
# main()
#
my ($func, $file, $lastslash);
while (my $line = <STDIN>) {
if ($line =~ m/$funcre/) {
$func = $1;
}
elsif ($line =~ m/(.*):\s*file format/) {
$file = $1;
$file =~ s/\.ko//;
$lastslash = rindex($file, "/");
if ($lastslash != -1) {
$file = substr($file, $lastslash + 1);
}
}
elsif ($line =~ m/$re/) {
my $size = $1;
$size = hex($size) if ($size =~ /^0x/);
if ($size > 0xf0000000) {
$size = - $size;
$size += 0x80000000;
$size += 0x80000000;
}
next if ($size > 0x10000000);
next if $line !~ m/^($xs*)/;
my $addr = $1;
$addr =~ s/ /0/g;
$addr = "0x$addr";
my $intro = "$addr $func [$file]:";
my $padlen = 56 - length($intro);
while ($padlen > 0) {
$intro .= ' ';
$padlen -= 8;
}
next if ($size < 100);
push @stack, "$intro$size\n";
}
elsif (defined $dre && $line =~ m/$dre/) {
my $size = "Dynamic ($1)";
next if $line !~ m/^($xs*)/;
my $addr = $1;
$addr =~ s/ /0/g;
$addr = "0x$addr";
my $intro = "$addr $func [$file]:";
my $padlen = 56 - length($intro);
while ($padlen > 0) {
$intro .= ' ';
$padlen -= 8;
}
push @stack, "$intro$size\n";
}
}
# Sort output by size (last field)
print sort { ($b =~ /:\t*(\d+)$/)[0] <=> ($a =~ /:\t*(\d+)$/)[0] } @stack;
Computing file changes ...
