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Revision 1e5de2837c166535f9bb4232bfe97ea1f9fc7a1c authored by Linus Torvalds on 08 July 2007, 19:02:55 UTC, committed by Linus Torvalds on 08 July 2007, 19:02:55 UTC 
Fix permission checking for the new utimensat() system call
 
Commit 1c710c896eb461895d3c399e15bb5f20b39c9073 added the utimensat()
system call, but didn't handle the case of checking for the writability
of the target right, when the target was a file descriptor, not a
filename.

We cannot use vfs_permission(MAY_WRITE) for that case, and need to
simply check whether the file descriptor is writable.  The oops from
using the wrong function was noticed and narrowed down by Markus
Trippelsdorf.

Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 4e99325
Raw File
extract-ikconfig 
#!/bin/sh
# extracts .config info from a [b]zImage file
# uses: binoffset (new), dd, zcat, strings, grep
# $arg1 is [b]zImage filename

binoffset="./scripts/binoffset"
test -e $binoffset || cc -o $binoffset ./scripts/binoffset.c || exit 1

IKCFG_ST="0x49 0x4b 0x43 0x46 0x47 0x5f 0x53 0x54"
IKCFG_ED="0x49 0x4b 0x43 0x46 0x47 0x5f 0x45 0x44"
function dump_config {
    typeset file="$1"

    start=`$binoffset $file $IKCFG_ST 2>/dev/null`
    [ "$?" != "0" ] && start="-1"
    if [ "$start" -eq "-1" ]; then
	return
    fi
    end=`$binoffset $file $IKCFG_ED 2>/dev/null`

    let start="$start + 8"
    let size="$end - $start"

    dd if="$file" ibs=1 skip="$start" count="$size" 2>/dev/null | zcat

    clean_up
    exit 0
}


usage()
{
	echo "  usage: extract-ikconfig [b]zImage_filename"
}

clean_up()
{
	if [ "$TMPFILE" != "" ]; then
		rm -f $TMPFILE
	fi
}

if [ $# -lt 1 ]
then
	usage
	exit 1
fi

TMPFILE=`mktemp -t ikconfig-XXXXXX` || exit 1
image="$1"

# vmlinux: Attempt to dump the configuration from the file directly
dump_config "$image"

GZHDR1="0x1f 0x8b 0x08 0x00"
GZHDR2="0x1f 0x8b 0x08 0x08"

# vmlinux.gz: Check for a compressed images
off=`$binoffset "$image" $GZHDR1 2>/dev/null`
[ "$?" != "0" ] && off="-1"
if [ "$off" -eq "-1" ]; then
	off=`$binoffset "$image" $GZHDR2 2>/dev/null`
	[ "$?" != "0" ] && off="-1"
fi
if [ "$off" -eq "0" ]; then
	zcat <"$image" >"$TMPFILE"
	dump_config "$TMPFILE"
elif [ "$off" -ne "-1" ]; then
	(dd ibs="$off" skip=1 count=0 && dd bs=512k) <"$image" 2>/dev/null | \
		zcat >"$TMPFILE"
	dump_config "$TMPFILE"
fi

echo "ERROR: Unable to extract kernel configuration information."
echo "       This kernel image may not have the config info."

clean_up
exit 1
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