mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

find dynamic stack allocations in checkstack.pl 

Currently, checkstack.pl only looks for fixed subtractions from the stack
pointer.  However, things like this:

void function(int size)
{
        char stackbuster[size << 2];
...

are certainly worth pointing out, I think.

This could perhaps be done more cleanly, and the following patch only
adds "dynamic" REs for x86 and x86_64, but it works:

0x00b0 crypto_cbc_decrypt_inplace [cbc]:                Dynamic (%rax)
0x00ad crypto_pcbc_decrypt_inplace [pcbc]:              Dynamic (%rax)
0x02f6 crypto_pcbc_encrypt_inplace [pcbc]:              Dynamic (%rax)
0x036c _crypto_xcbc_digest_setkey [xcbc]:               Dynamic (%rax)
...

(Inspired by Keith Owens' old stack-check script)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Eric Sandeen 2008-07-25 01:45:27 -07:00 committed by Linus Torvalds
parent 545e400619
commit 585e93ae83
1 changed files with 23 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
scripts/checkstack.pl
View File

@ -26,8 +26,12 @@
# $& (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, $x, $xs);
my (@stack, $re, $dre, $x, $xs);
{
my $arch = shift;
if ($arch eq "") {
@ -46,9 +50,11 @@ my (@stack, $re, $x, $xs);
} elsif ($arch =~ /^i[3456]86$/) {
#c0105234: 81 ec ac 05 00 00 sub $0x5ac,%esp
$re = qr/^.*[as][du][db] \$(0x$x{1,8}),\%esp$/o;
$dre = qr/^.*[as][du][db] (%.*),\%esp$/o;
} elsif ($arch eq 'x86_64') {
# 2f60: 48 81 ec e8 05 00 00 sub $0x5e8,%rsp
$re = qr/^.*[as][du][db] \$(0x$x{1,8}),\%rsp$/o;
$dre = qr/^.*[as][du][db] (\%.*),\%rsp$/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;
@ -141,6 +147,22 @@ while (my $line = <STDIN>) {
next if ($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";
}
}
print sort bysize @stack;