[PATCH v2 5/9] block: Switch struct packet_command to use struct scsi_sense_hdr

From: Kees Cook
Date: Tue Jul 31 2018 - 15:52:23 EST

There is a lot of needless struct request_sense usage in the CDROM
code. These can all be struct scsi_sense_hdr instead, to avoid any
confusion over their respective structure sizes. This patch is a lot
of noise changing "sense" to "sshdr", but the final code is more
readable to distinguish between "sense" meaning "struct request_sense"
and "sshdr" meaning "struct scsi_sense_hdr".

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
drivers/block/pktcdvd.c | 36 ++++++++++++++++++------------------
drivers/cdrom/cdrom.c | 22 +++++++++++-----------
drivers/ide/ide-cd.c | 11 ++++++-----
drivers/ide/ide-cd.h | 4 ++--
drivers/ide/ide-cd_ioctl.c | 30 +++++++++++++++---------------
drivers/scsi/sr_ioctl.c | 22 +++++++++-------------
include/linux/cdrom.h | 3 ++-
7 files changed, 63 insertions(+), 65 deletions(-)

diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index c61d20c9f3f8..f91c9f85e29d 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -748,13 +748,13 @@ static const char *sense_key_string(__u8 index)
static void pkt_dump_sense(struct pktcdvd_device *pd,
struct packet_command *cgc)
{
- struct request_sense *sense = cgc->sense;
+ struct scsi_sense_hdr *sshdr = cgc->sshdr;

- if (sense)
+ if (sshdr)
pkt_err(pd, "%*ph - sense %02x.%02x.%02x (%s)\n",
CDROM_PACKET_SIZE, cgc->cmd,
- sense->sense_key, sense->asc, sense->ascq,
- sense_key_string(sense->sense_key));
+ sshdr->sense_key, sshdr->asc, sshdr->ascq,
+ sense_key_string(sshdr->sense_key));
else
pkt_err(pd, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
}
@@ -787,11 +787,11 @@ static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
unsigned write_speed, unsigned read_speed)
{
struct packet_command cgc;
- struct request_sense sense;
+ struct scsi_sense_hdr sshdr;
int ret;

init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
- cgc.sense = &sense;
+ cgc.sshdr = &sshdr;
cgc.cmd[0] = GPCMD_SET_SPEED;
cgc.cmd[2] = (read_speed >> 8) & 0xff;
cgc.cmd[3] = read_speed & 0xff;
@@ -1645,7 +1645,7 @@ static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
{
struct packet_command cgc;
- struct request_sense sense;
+ struct scsi_sense_hdr sshdr;
write_param_page *wp;
char buffer[128];
int ret, size;
@@ -1656,7 +1656,7 @@ static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)

memset(buffer, 0, sizeof(buffer));
init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
- cgc.sense = &sense;
+ cgc.sshdr = &sshdr;
if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
pkt_dump_sense(pd, &cgc);
return ret;
@@ -1671,7 +1671,7 @@ static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
* now get it all
*/
init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
- cgc.sense = &sense;
+ cgc.sshdr = &sshdr;
if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
pkt_dump_sense(pd, &cgc);
return ret;
@@ -1905,12 +1905,12 @@ static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
int set)
{
struct packet_command cgc;
- struct request_sense sense;
+ struct scsi_sense_hdr sshdr;
unsigned char buf[64];
int ret;

init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
- cgc.sense = &sense;
+ cgc.sshdr = &sshdr;
cgc.buflen = pd->mode_offset + 12;

/*
@@ -1950,14 +1950,14 @@ static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
unsigned *write_speed)
{
struct packet_command cgc;
- struct request_sense sense;
+ struct scsi_sense_hdr sshdr;
unsigned char buf[256+18];
unsigned char *cap_buf;
int ret, offset;

cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
- cgc.sense = &sense;
+ cgc.sshdr = &sshdr;

ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
if (ret) {
@@ -2011,13 +2011,13 @@ static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
unsigned *speed)
{
struct packet_command cgc;
- struct request_sense sense;
+ struct scsi_sense_hdr sshdr;
unsigned char buf[64];
unsigned int size, st, sp;
int ret;

init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
- cgc.sense = &sense;
+ cgc.sshdr = &sshdr;
cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
cgc.cmd[1] = 2;
cgc.cmd[2] = 4; /* READ ATIP */
@@ -2032,7 +2032,7 @@ static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
size = sizeof(buf);

init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
- cgc.sense = &sense;
+ cgc.sshdr = &sshdr;
cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
cgc.cmd[1] = 2;
cgc.cmd[2] = 4;
@@ -2083,13 +2083,13 @@ static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
{
struct packet_command cgc;
- struct request_sense sense;
+ struct scsi_sense_hdr sshdr;
int ret;

pkt_dbg(2, pd, "Performing OPC\n");

init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
- cgc.sense = &sense;
+ cgc.sshdr = &sshdr;
cgc.timeout = 60*HZ;
cgc.cmd[0] = GPCMD_SEND_OPC;
cgc.cmd[1] = 1;
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index bfc566d3f31a..3522d2cae1b6 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -345,10 +345,10 @@ static LIST_HEAD(cdrom_list);
int cdrom_dummy_generic_packet(struct cdrom_device_info *cdi,
struct packet_command *cgc)
{
- if (cgc->sense) {
- cgc->sense->sense_key = 0x05;
- cgc->sense->asc = 0x20;
- cgc->sense->ascq = 0x00;
+ if (cgc->sshdr) {
+ cgc->sshdr->sense_key = 0x05;
+ cgc->sshdr->asc = 0x20;
+ cgc->sshdr->ascq = 0x00;
}

cgc->stat = -EIO;
@@ -2943,7 +2943,7 @@ static noinline int mmc_ioctl_cdrom_read_data(struct cdrom_device_info *cdi,
struct packet_command *cgc,
int cmd)
{
- struct request_sense sense;
+ struct scsi_sense_hdr sshdr;
struct cdrom_msf msf;
int blocksize = 0, format = 0, lba;
int ret;
@@ -2971,13 +2971,13 @@ static noinline int mmc_ioctl_cdrom_read_data(struct cdrom_device_info *cdi,
if (cgc->buffer == NULL)
return -ENOMEM;

- memset(&sense, 0, sizeof(sense));
- cgc->sense = &sense;
+ memset(&sshdr, 0, sizeof(sshdr));
+ cgc->sshdr = &sshdr;
cgc->data_direction = CGC_DATA_READ;
ret = cdrom_read_block(cdi, cgc, lba, 1, format, blocksize);
- if (ret && sense.sense_key == 0x05 &&
- sense.asc == 0x20 &&
- sense.ascq == 0x00) {
+ if (ret && sshdr.sense_key == 0x05 &&
+ sshdr.asc == 0x20 &&
+ sshdr.ascq == 0x00) {
/*
* SCSI-II devices are not required to support
* READ_CD, so let's try switching block size
@@ -2986,7 +2986,7 @@ static noinline int mmc_ioctl_cdrom_read_data(struct cdrom_device_info *cdi,
ret = cdrom_switch_blocksize(cdi, blocksize);
if (ret)
goto out;
- cgc->sense = NULL;
+ cgc->sshdr = NULL;
ret = cdrom_read_cd(cdi, cgc, lba, blocksize, 1);
ret |= cdrom_switch_blocksize(cdi, blocksize);
}
diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
index 1d5b35312e33..cb90560acf6e 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -419,7 +419,7 @@ static void ide_cd_request_sense_fixup(ide_drive_t *drive, struct ide_cmd *cmd)

int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,
int write, void *buffer, unsigned *bufflen,
- struct request_sense *sense, int timeout,
+ struct scsi_sense_hdr *sshdr, int timeout,
req_flags_t rq_flags)
{
struct cdrom_info *info = drive->driver_data;
@@ -456,8 +456,9 @@ int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,

if (buffer)
*bufflen = scsi_req(rq)->resid_len;
- if (sense)
- memcpy(sense, scsi_req(rq)->sense, sizeof(*sense));
+ if (sshdr)
+ scsi_normalize_sense(scsi_req(rq)->sense,
+ scsi_req(rq)->sense_len, sshdr);

/*
* FIXME: we should probably abort/retry or something in case of
@@ -864,7 +865,7 @@ static void msf_from_bcd(struct atapi_msf *msf)
msf->frame = bcd2bin(msf->frame);
}

-int cdrom_check_status(ide_drive_t *drive, struct request_sense *sense)
+int cdrom_check_status(ide_drive_t *drive, struct scsi_sense_hdr *sshdr)
{
struct cdrom_info *info = drive->driver_data;
struct cdrom_device_info *cdi;
@@ -886,7 +887,7 @@ int cdrom_check_status(ide_drive_t *drive, struct request_sense *sense)
*/
cmd[7] = cdi->sanyo_slot % 3;

- return ide_cd_queue_pc(drive, cmd, 0, NULL, NULL, sense, 0, RQF_QUIET);
+ return ide_cd_queue_pc(drive, cmd, 0, NULL, NULL, sshdr, 0, RQF_QUIET);
}

static int cdrom_read_capacity(ide_drive_t *drive, unsigned long *capacity,
diff --git a/drivers/ide/ide-cd.h b/drivers/ide/ide-cd.h
index fc162fbb6629..a69dc7f61c4d 100644
--- a/drivers/ide/ide-cd.h
+++ b/drivers/ide/ide-cd.h
@@ -98,11 +98,11 @@ void ide_cd_log_error(const char *, struct request *, struct request_sense *);

/* ide-cd.c functions used by ide-cd_ioctl.c */
int ide_cd_queue_pc(ide_drive_t *, const unsigned char *, int, void *,
- unsigned *, struct request_sense *, int, req_flags_t);
+ unsigned *, struct scsi_sense_hdr *, int, req_flags_t);
int ide_cd_read_toc(ide_drive_t *);
int ide_cdrom_get_capabilities(ide_drive_t *, u8 *);
void ide_cdrom_update_speed(ide_drive_t *, u8 *);
-int cdrom_check_status(ide_drive_t *, struct request_sense *);
+int cdrom_check_status(ide_drive_t *, struct scsi_sense_hdr *);

/* ide-cd_ioctl.c */
int ide_cdrom_open_real(struct cdrom_device_info *, int);
diff --git a/drivers/ide/ide-cd_ioctl.c b/drivers/ide/ide-cd_ioctl.c
index c709f4eed0e9..c945beb9e75a 100644
--- a/drivers/ide/ide-cd_ioctl.c
+++ b/drivers/ide/ide-cd_ioctl.c
@@ -43,14 +43,14 @@ int ide_cdrom_drive_status(struct cdrom_device_info *cdi, int slot_nr)
{
ide_drive_t *drive = cdi->handle;
struct media_event_desc med;
- struct request_sense sense;
+ struct scsi_sense_hdr sshdr;
int stat;

if (slot_nr != CDSL_CURRENT)
return -EINVAL;

- stat = cdrom_check_status(drive, &sense);
- if (!stat || sense.sense_key == UNIT_ATTENTION)
+ stat = cdrom_check_status(drive, &sshdr);
+ if (!stat || sshdr.sense_key == UNIT_ATTENTION)
return CDS_DISC_OK;

if (!cdrom_get_media_event(cdi, &med)) {
@@ -62,8 +62,8 @@ int ide_cdrom_drive_status(struct cdrom_device_info *cdi, int slot_nr)
return CDS_NO_DISC;
}

- if (sense.sense_key == NOT_READY && sense.asc == 0x04
- && sense.ascq == 0x04)
+ if (sshdr.sense_key == NOT_READY && sshdr.asc == 0x04
+ && sshdr.ascq == 0x04)
return CDS_DISC_OK;

/*
@@ -71,8 +71,8 @@ int ide_cdrom_drive_status(struct cdrom_device_info *cdi, int slot_nr)
* just return TRAY_OPEN since ATAPI doesn't provide
* any other way to detect this...
*/
- if (sense.sense_key == NOT_READY) {
- if (sense.asc == 0x3a && sense.ascq == 1)
+ if (sshdr.sense_key == NOT_READY) {
+ if (sshdr.asc == 0x3a && sshdr.ascq == 1)
return CDS_NO_DISC;
else
return CDS_TRAY_OPEN;
@@ -135,7 +135,7 @@ int cdrom_eject(ide_drive_t *drive, int ejectflag)
static
int ide_cd_lockdoor(ide_drive_t *drive, int lockflag)
{
- struct request_sense my_sense, *sense = &my_sense;
+ struct scsi_sense_hdr sshdr;
int stat;

/* If the drive cannot lock the door, just pretend. */
@@ -150,14 +150,14 @@ int ide_cd_lockdoor(ide_drive_t *drive, int lockflag)
cmd[4] = lockflag ? 1 : 0;

stat = ide_cd_queue_pc(drive, cmd, 0, NULL, NULL,
- sense, 0, 0);
+ &sshdr, 0, 0);
}

/* If we got an illegal field error, the drive
probably cannot lock the door. */
if (stat != 0 &&
- sense->sense_key == ILLEGAL_REQUEST &&
- (sense->asc == 0x24 || sense->asc == 0x20)) {
+ sshdr.sense_key == ILLEGAL_REQUEST &&
+ (sshdr.asc == 0x24 || sshdr.asc == 0x20)) {
printk(KERN_ERR "%s: door locking not supported\n",
drive->name);
drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING;
@@ -165,7 +165,7 @@ int ide_cd_lockdoor(ide_drive_t *drive, int lockflag)
}

/* no medium, that's alright. */
- if (stat != 0 && sense->sense_key == NOT_READY && sense->asc == 0x3a)
+ if (stat != 0 && sshdr.sense_key == NOT_READY && sshdr.asc == 0x3a)
stat = 0;

if (stat == 0) {
@@ -451,8 +451,8 @@ int ide_cdrom_packet(struct cdrom_device_info *cdi,
layer. the packet must be complete, as we do not
touch it at all. */

- if (cgc->sense)
- memset(cgc->sense, 0, sizeof(struct request_sense));
+ if (cgc->sshdr)
+ memset(cgc->sshdr, 0, sizeof(*cgc->sshdr));

if (cgc->quiet)
flags |= RQF_QUIET;
@@ -460,7 +460,7 @@ int ide_cdrom_packet(struct cdrom_device_info *cdi,
cgc->stat = ide_cd_queue_pc(drive, cgc->cmd,
cgc->data_direction == CGC_DATA_WRITE,
cgc->buffer, &len,
- cgc->sense, cgc->timeout, flags);
+ cgc->sshdr, cgc->timeout, flags);
if (!cgc->stat)
cgc->buflen -= len;
return cgc->stat;
diff --git a/drivers/scsi/sr_ioctl.c b/drivers/scsi/sr_ioctl.c
index 35fab1e18adc..ffcf902da390 100644
--- a/drivers/scsi/sr_ioctl.c
+++ b/drivers/scsi/sr_ioctl.c
@@ -186,14 +186,13 @@ static int sr_play_trkind(struct cdrom_device_info *cdi,
int sr_do_ioctl(Scsi_CD *cd, struct packet_command *cgc)
{
struct scsi_device *SDev;
- struct scsi_sense_hdr sshdr;
+ struct scsi_sense_hdr local_sshdr, *sshdr = &local_sshdr;
int result, err = 0, retries = 0;
- unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE], *senseptr = NULL;

SDev = cd->device;

- if (cgc->sense)
- senseptr = sense_buffer;
+ if (cgc->sshdr)
+ sshdr = cgc->sshdr;

retry:
if (!scsi_block_when_processing_errors(SDev)) {
@@ -202,15 +201,12 @@ int sr_do_ioctl(Scsi_CD *cd, struct packet_command *cgc)
}

result = scsi_execute(SDev, cgc->cmd, cgc->data_direction,
- cgc->buffer, cgc->buflen, senseptr, &sshdr,
+ cgc->buffer, cgc->buflen, NULL, sshdr,
cgc->timeout, IOCTL_RETRIES, 0, 0, NULL);

- if (cgc->sense)
- memcpy(cgc->sense, sense_buffer, sizeof(*cgc->sense));
-
/* Minimal error checking. Ignore cases we know about, and report the rest. */
if (driver_byte(result) != 0) {
- switch (sshdr.sense_key) {
+ switch (sshdr->sense_key) {
case UNIT_ATTENTION:
SDev->changed = 1;
if (!cgc->quiet)
@@ -221,8 +217,8 @@ int sr_do_ioctl(Scsi_CD *cd, struct packet_command *cgc)
err = -ENOMEDIUM;
break;
case NOT_READY: /* This happens if there is no disc in drive */
- if (sshdr.asc == 0x04 &&
- sshdr.ascq == 0x01) {
+ if (sshdr->asc == 0x04 &&
+ sshdr->ascq == 0x01) {
/* sense: Logical unit is in process of becoming ready */
if (!cgc->quiet)
sr_printk(KERN_INFO, cd,
@@ -245,8 +241,8 @@ int sr_do_ioctl(Scsi_CD *cd, struct packet_command *cgc)
break;
case ILLEGAL_REQUEST:
err = -EIO;
- if (sshdr.asc == 0x20 &&
- sshdr.ascq == 0x00)
+ if (sshdr->asc == 0x20 &&
+ sshdr->ascq == 0x00)
/* sense: Invalid command operation code */
err = -EDRIVE_CANT_DO_THIS;
break;
diff --git a/include/linux/cdrom.h b/include/linux/cdrom.h
index e75dfd1f1dec..528271c60018 100644
--- a/include/linux/cdrom.h
+++ b/include/linux/cdrom.h
@@ -13,6 +13,7 @@

#include <linux/fs.h> /* not really needed, later.. */
#include <linux/list.h>
+#include <scsi/scsi_common.h>
#include <uapi/linux/cdrom.h>

struct packet_command
@@ -21,7 +22,7 @@ struct packet_command
unsigned char *buffer;
unsigned int buflen;
int stat;
- struct request_sense *sense;
+ struct scsi_sense_hdr *sshdr;
unsigned char data_direction;
int quiet;
int timeout;
--
2.17.1