kexec-tools/dracut-kdump.sh
Tao Liu 910c20d3ce Fix incorrect vmcore permissions when dumped through ssh
Related: rhbz#1938165
Upstream: fedora
Conflict: none

commit 00785873ef
Author: Tao Liu <ltao@redhat.com>
Date:   Fri Mar 19 18:07:51 2021 +0800

    Fix incorrect vmcore permissions when dumped through ssh

    Previously when dumping vmcore to a remote machine through ssh,
    the files are created remotely and file permissions are taken
    from the default umask value, which making the files accessible to
    anyone on the remote machine.

    This patch fixed the security issue by setting a customized umask value
    before the file creation on the remote machine.

    Signed-off-by: Tao Liu <ltao@redhat.com>
    Acked-by: Kairui Song <kasong@redhat.com>

Signed-off-by: Tao Liu <ltao@redhat.com>
2021-04-20 16:29:34 +08:00

325 lines
7.9 KiB
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Executable File

#!/bin/sh
# continue here only if we have to save dump.
if [ -f /etc/fadump.initramfs ] && [ ! -f /proc/device-tree/rtas/ibm,kernel-dump ] && [ ! -f /proc/device-tree/ibm,opal/dump/mpipl-boot ]; then
exit 0
fi
. /lib/dracut-lib.sh
. /lib/kdump-lib-initramfs.sh
set -o pipefail
DUMP_RETVAL=0
export PATH=$PATH:$KDUMP_SCRIPT_DIR
do_dump()
{
local _ret
eval $DUMP_INSTRUCTION
_ret=$?
if [ $_ret -ne 0 ]; then
derror "saving vmcore failed"
fi
return $_ret
}
do_kdump_pre()
{
local _ret
if [ -n "$KDUMP_PRE" ]; then
"$KDUMP_PRE"
_ret=$?
if [ $_ret -ne 0 ]; then
derror "$KDUMP_PRE exited with $_ret status"
return $_ret
fi
fi
# if any script fails, it just raises warning and continues
if [ -d /etc/kdump/pre.d ]; then
for file in /etc/kdump/pre.d/*; do
"$file"
_ret=$?
if [ $_ret -ne 0 ]; then
derror "$file exited with $_ret status"
fi
done
fi
return 0
}
do_kdump_post()
{
local _ret
if [ -d /etc/kdump/post.d ]; then
for file in /etc/kdump/post.d/*; do
"$file" "$1"
_ret=$?
if [ $_ret -ne 0 ]; then
derror "$file exited with $_ret status"
fi
done
fi
if [ -n "$KDUMP_POST" ]; then
"$KDUMP_POST" "$1"
_ret=$?
if [ $_ret -ne 0 ]; then
derror "$KDUMP_POST exited with $_ret status"
fi
fi
}
add_dump_code()
{
DUMP_INSTRUCTION=$1
}
dump_raw()
{
local _raw=$1
[ -b "$_raw" ] || return 1
dinfo "saving to raw disk $_raw"
if ! $(echo -n $CORE_COLLECTOR|grep -q makedumpfile); then
_src_size=`ls -l /proc/vmcore | cut -d' ' -f5`
_src_size_mb=$(($_src_size / 1048576))
monitor_dd_progress $_src_size_mb &
fi
dinfo "saving vmcore"
$CORE_COLLECTOR /proc/vmcore | dd of=$_raw bs=$DD_BLKSIZE >> /tmp/dd_progress_file 2>&1 || return 1
sync
dinfo "saving vmcore complete"
return 0
}
dump_ssh()
{
local _ret=0
local _exitcode=0 _exitcode2=0
local _opt="-i $1 -o BatchMode=yes -o StrictHostKeyChecking=yes"
local _dir="$KDUMP_PATH/$HOST_IP-$DATEDIR"
local _host=$2
local _vmcore="vmcore"
local _ipv6_addr="" _username=""
dinfo "saving to $_host:$_dir"
cat /var/lib/random-seed > /dev/urandom
ssh -q $_opt $_host mkdir -p $_dir || return 1
save_vmcore_dmesg_ssh ${DMESG_COLLECTOR} ${_dir} "${_opt}" $_host
save_opalcore_ssh ${_dir} "${_opt}" $_host
dinfo "saving vmcore"
if is_ipv6_address "$_host"; then
_username=${_host%@*}
_ipv6_addr="[${_host#*@}]"
fi
if [ "${CORE_COLLECTOR%%[[:blank:]]*}" = "scp" ]; then
if [ -n "$_username" ] && [ -n "$_ipv6_addr" ]; then
scp -q $_opt /proc/vmcore "$_username@$_ipv6_addr:$_dir/vmcore-incomplete"
else
scp -q $_opt /proc/vmcore "$_host:$_dir/vmcore-incomplete"
fi
_exitcode=$?
else
$CORE_COLLECTOR /proc/vmcore | ssh $_opt $_host "umask 0077 && dd bs=512 of=$_dir/vmcore-incomplete"
_exitcode=$?
_vmcore="vmcore.flat"
fi
if [ $_exitcode -eq 0 ]; then
ssh $_opt $_host "mv $_dir/vmcore-incomplete $_dir/$_vmcore"
_exitcode2=$?
if [ $_exitcode2 -ne 0 ]; then
derror "moving vmcore failed, _exitcode:$_exitcode2"
else
dinfo "saving vmcore complete"
fi
else
derror "saving vmcore failed, _exitcode:$_exitcode"
fi
dinfo "saving the $KDUMP_LOG_FILE to $_host:$_dir/"
save_log
if [ -n "$_username" ] && [ -n "$_ipv6_addr" ]; then
scp -q $_opt $KDUMP_LOG_FILE "$_username@$_ipv6_addr:$_dir/"
else
scp -q $_opt $KDUMP_LOG_FILE "$_host:$_dir/"
fi
_ret=$?
if [ $_ret -ne 0 ]; then
derror "saving log file failed, _exitcode:$_ret"
fi
if [ $_exitcode -ne 0 ] || [ $_exitcode2 -ne 0 ];then
return 1
fi
return 0
}
save_opalcore_ssh() {
local _path=$1
local _opts="$2"
local _location=$3
local _user_name="" _ipv6addr=""
ddebug "_path=$_path _opts=$_opts _location=$_location"
if [ ! -f $OPALCORE ]; then
# Check if we are on an old kernel that uses a different path
if [ -f /sys/firmware/opal/core ]; then
OPALCORE="/sys/firmware/opal/core"
else
return 0
fi
fi
if is_ipv6_address "$_host"; then
_user_name=${_location%@*}
_ipv6addr="[${_location#*@}]"
fi
dinfo "saving opalcore:$OPALCORE to $_location:$_path"
if [ -n "$_user_name" ] && [ -n "$_ipv6addr" ]; then
scp $_opts $OPALCORE $_user_name@$_ipv6addr:$_path/opalcore-incomplete
else
scp $_opts $OPALCORE $_location:$_path/opalcore-incomplete
fi
if [ $? -ne 0 ]; then
derror "saving opalcore failed"
return 1
fi
ssh $_opts $_location mv $_path/opalcore-incomplete $_path/opalcore
dinfo "saving opalcore complete"
return 0
}
save_vmcore_dmesg_ssh() {
local _dmesg_collector=$1
local _path=$2
local _opts="$3"
local _location=$4
dinfo "saving vmcore-dmesg.txt to $_location:$_path"
$_dmesg_collector /proc/vmcore | ssh $_opts $_location "umask 0077 && dd of=$_path/vmcore-dmesg-incomplete.txt"
_exitcode=$?
if [ $_exitcode -eq 0 ]; then
ssh -q $_opts $_location mv $_path/vmcore-dmesg-incomplete.txt $_path/vmcore-dmesg.txt
dinfo "saving vmcore-dmesg.txt complete"
else
derror "saving vmcore-dmesg.txt failed"
fi
}
get_host_ip()
{
local _host
if is_nfs_dump_target || is_ssh_dump_target
then
kdumpnic=$(getarg kdumpnic=)
[ -z "$kdumpnic" ] && derror "failed to get kdumpnic!" && return 1
_host=`ip addr show dev $kdumpnic|grep '[ ]*inet'`
[ $? -ne 0 ] && derror "wrong kdumpnic: $kdumpnic" && return 1
_host=`echo $_host | head -n 1 | cut -d' ' -f2`
_host="${_host%%/*}"
[ -z "$_host" ] && derror "wrong kdumpnic: $kdumpnic" && return 1
HOST_IP=$_host
fi
return 0
}
read_kdump_conf()
{
if [ ! -f "$KDUMP_CONF" ]; then
derror "$KDUMP_CONF not found"
return
fi
get_kdump_confs
# rescan for add code for dump target
while read config_opt config_val;
do
# remove inline comments after the end of a directive.
case "$config_opt" in
dracut_args)
config_val=$(get_dracut_args_target "$config_val")
if [ -n "$config_val" ]; then
config_val=$(get_mntpoint_from_target "$config_val")
add_dump_code "dump_fs $config_val"
fi
;;
ext[234]|xfs|btrfs|minix|nfs)
config_val=$(get_mntpoint_from_target "$config_val")
add_dump_code "dump_fs $config_val"
;;
raw)
add_dump_code "dump_raw $config_val"
;;
ssh)
add_dump_code "dump_ssh $SSH_KEY_LOCATION $config_val"
;;
esac
done <<< "$(read_strip_comments $KDUMP_CONF)"
}
fence_kdump_notify()
{
if [ -n "$FENCE_KDUMP_NODES" ]; then
$FENCE_KDUMP_SEND $FENCE_KDUMP_ARGS $FENCE_KDUMP_NODES &
fi
}
read_kdump_conf
fence_kdump_notify
get_host_ip
if [ $? -ne 0 ]; then
derror "get_host_ip exited with non-zero status!"
exit 1
fi
if [ -z "$DUMP_INSTRUCTION" ]; then
add_dump_code "dump_fs $NEWROOT"
fi
do_kdump_pre
if [ $? -ne 0 ]; then
derror "kdump_pre script exited with non-zero status!"
do_final_action
# During systemd service to reboot the machine, stop this shell script running
exit 1
fi
make_trace_mem "kdump saving vmcore" '1:shortmem' '2+:mem' '3+:slab'
do_dump
DUMP_RETVAL=$?
do_kdump_post $DUMP_RETVAL
if [ $? -ne 0 ]; then
derror "kdump_post script exited with non-zero status!"
fi
if [ $DUMP_RETVAL -ne 0 ]; then
exit 1
fi
do_final_action