diff options
| author | Stefan Haberland <stefan.haberland@de.ibm.com> | 2015-10-15 11:10:08 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2015-11-03 14:40:44 +0100 |
| commit | c7c0c9deb0a4b0715d2c09438420437b86f387c4 (patch) | |
| tree | 9144935f736ed2457fe09a12d0305b26eed1d98a /drivers/s390 | |
| parent | s390/kernel: fix ptrace peek/poke for floating point registers (diff) | |
| download | linux-c7c0c9deb0a4b0715d2c09438420437b86f387c4.tar.xz linux-c7c0c9deb0a4b0715d2c09438420437b86f387c4.zip | |
s390/dasd: fix double free in dasd_eckd_read_conf
The configuration data is stored per path and also the first valid
configuration data per device. When dasd_eckd_read_conf is called
again after a path got lost the device configuration data is cleared
but possibly not the per path configuration data. This might lead to a
double free when the lost path gets operational again.
Fix by clearing all per path configuration data when the first valid
configuration data is received and stored.
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390')
| -rw-r--r-- | drivers/s390/block/dasd_eckd.c | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index 30c2a80c004b..e53b895a4d0f 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -1032,6 +1032,21 @@ static unsigned char dasd_eckd_path_access(void *conf_data, int conf_len) return 0; } +static void dasd_eckd_clear_conf_data(struct dasd_device *device) +{ + struct dasd_eckd_private *private; + int i; + + private = (struct dasd_eckd_private *) device->private; + private->conf_data = NULL; + private->conf_len = 0; + for (i = 0; i < 8; i++) { + kfree(private->path_conf_data[i]); + private->path_conf_data[i] = NULL; + } +} + + static int dasd_eckd_read_conf(struct dasd_device *device) { void *conf_data; @@ -1068,19 +1083,10 @@ static int dasd_eckd_read_conf(struct dasd_device *device) path_data->opm |= lpm; continue; /* no error */ } - pos = pathmask_to_pos(lpm); - kfree(private->path_conf_data[pos]); - if ((__u8 *)private->path_conf_data[pos] == - private->conf_data) { - private->conf_data = NULL; - private->conf_len = 0; - conf_data_saved = 0; - } - private->path_conf_data[pos] = - (struct dasd_conf_data *) conf_data; /* save first valid configuration data */ if (!conf_data_saved) { - kfree(private->conf_data); + /* initially clear previously stored conf_data */ + dasd_eckd_clear_conf_data(device); private->conf_data = conf_data; private->conf_len = conf_len; if (dasd_eckd_identify_conf_parts(private)) { @@ -1089,6 +1095,10 @@ static int dasd_eckd_read_conf(struct dasd_device *device) kfree(conf_data); continue; } + pos = pathmask_to_pos(lpm); + /* store per path conf_data */ + private->path_conf_data[pos] = + (struct dasd_conf_data *) conf_data; /* * build device UID that other path data * can be compared to it @@ -1146,7 +1156,10 @@ static int dasd_eckd_read_conf(struct dasd_device *device) path_data->cablepm |= lpm; continue; } - + pos = pathmask_to_pos(lpm); + /* store per path conf_data */ + private->path_conf_data[pos] = + (struct dasd_conf_data *) conf_data; path_private.conf_data = NULL; path_private.conf_len = 0; } |