Re: [4KSTACK][2.6.6] Stack overflow in radeonfb

From: Arjan van de Ven
Date: Fri May 14 2004 - 04:51:37 EST


On Fri, May 14, 2004 at 11:47:39AM +0200, Andrew Morton wrote:
> There's a `make buildcheck' target in -mm (from Arjan) into which we could
> integrate such a tool. Although probably it should be a different make
> target.

I added it to buildcheck for now, based on Keith Owens' check-stack.sh
script. I added a tiny bit of perl (shudder) to it to
1) Make it print in decimal not hex
2) Filter the stack users to users of 400 bytes and higher

I arbitrarily used 400; that surely is debatable.

Greetings,
Arjan van de Ven

diff -purN linux-2.6.6/Makefile linux/Makefile
--- linux-2.6.6/Makefile 2004-05-14 09:22:43.735077088 +0200
+++ linux/Makefile 2004-05-14 11:44:40.277365864 +0200
@@ -1061,6 +1061,8 @@ versioncheck:

buildcheck:
$(PERL) scripts/reference_discarded.pl
+ sh scripts/check-stack.sh vmlinux
+ find -name "*.ko" | xargs sh scripts/check-stack.sh

endif #ifeq ($(config-targets),1)
endif #ifeq ($(mixed-targets),1)
diff -purN linux-2.6.6/scripts/check-stack.sh linux/scripts/check-stack.sh
--- linux-2.6.6/scripts/check-stack.sh 1970-01-01 01:00:00.000000000 +0100
+++ linux/scripts/check-stack.sh 2004-05-14 11:43:12.484712376 +0200
@@ -0,0 +1,47 @@
+#!/bin/bash
+#
+# Written by Keith Owens, modified by Arjan van de Ven to output in deciman
+#
+# Usage : check-stack.sh vmlinux $(/sbin/modprobe -l)
+#
+# Run a compiled ix86 kernel and print large local stack usage.
+#
+# />:/{s/[<>:]*//g; h; } On lines that contain '>:' (headings like
+# c0100000 <_stext>:), remove <, > and : and hold the line. Identifies
+# the procedure and its start address.
+#
+# /subl\?.*\$0x[^,][^,][^,].*,%esp/{ Select lines containing
+# subl\?...0x...,%esp but only if there are at least 3 digits between 0x and
+# ,%esp. These are local stacks of at least 0x100 bytes.
+#
+# s/.*$0x\([^,]*\).*/\1/; Extract just the stack adjustment
+# /^[89a-f].......$/d; Ignore line with 8 digit offsets that are
+# negative. Some compilers adjust the stack on exit, seems to be related
+# to goto statements
+# G; Append the held line (procedure and start address).
+# s/\(.*\)\n.* \(.*\)/\1 \2/; Remove the newline and procedure start
+# address. Leaves just stack size and procedure name.
+# p; }; Print stack size and procedure name.
+#
+# /subl\?.*%.*,%esp/{ Selects adjustment of %esp by register, dynamic
+# arrays on stack.
+# G; Append the held line (procedure and start address).
+# s/\(.*\)\n\(.*\)/Dynamic \2 \1/; Reformat to "Dynamic", procedure
+# start address, procedure name and the instruction that adjusts the
+# stack, including its offset within the proc.
+# p; }; Print the dynamic line.
+#
+#
+# Leading spaces in the sed string are required.
+#
+# first check if it's x86, since only that arch works for now
+file vmlinux | grep 80386 > /dev/null || exit
+#
+objdump --disassemble "$@" | \
+sed -ne '/>:/{s/[<>:]*//g; h; }
+ /subl\?.*\$0x[^,][^,][^,].*,%esp/{
+ s/.*\$0x\([^,]*\).*/\1/; /^[89a-f].......$/d; G; s/\(.*\)\n.* \(.*\)/\1 \2/; p; };
+ /subl\?.*%.*,%esp/{ G; s/\(.*\)\n\(.*\)/Dynamic \2 \1/; p; }; ' | \
+ sort | \
+perl -e 'while (<>) { if (/^([0-9a-f]+)(.*)/) { $decn = hex("0x" . $1); if ($decn > 400) { print "$decn $2\n";} } }'
+
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/