From: Damien Le Moal Date: Fri, 2 Mar 2018 07:19:28 +0900 Subject: scsi: sd_zbc: Fix potential memory leak Git-commit: 4b433924b2755a94f99258c178684a0e05c344de Patch-mainline: v4.16-rc6 References: git-fixes bsc#1118139 Rework sd_zbc_check_zone_size() to avoid a memory leak due to an early return if sd_zbc_report_zones() fails. Reported-by: David.butterfield Signed-off-by: Damien Le Moal Cc: stable@vger.kernel.org Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen Acked-by: Lee Duncan --- drivers/scsi/sd_zbc.c | 35 +++++++++++++++-------------------- 1 file changed, 15 insertions(+), 20 deletions(-) diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c index 27793b9f54c0..9049a189c8e5 100644 --- a/drivers/scsi/sd_zbc.c +++ b/drivers/scsi/sd_zbc.c @@ -486,7 +486,7 @@ static int sd_zbc_check_capacity(struct scsi_disk *sdkp, unsigned char *buf) */ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp) { - u64 zone_blocks; + u64 zone_blocks = 0; sector_t block = 0; unsigned char *buf; unsigned char *rec; @@ -504,10 +504,8 @@ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp) /* Do a report zone to get the same field */ ret = sd_zbc_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE, 0); - if (ret) { - zone_blocks = 0; - goto out; - } + if (ret) + goto out_free; same = buf[4] & 0x0f; if (same > 0) { @@ -547,7 +545,7 @@ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp) ret = sd_zbc_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE, block); if (ret) - return ret; + goto out_free; } } while (block < sdkp->capacity); @@ -555,35 +553,32 @@ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp) zone_blocks = sdkp->zone_blocks; out: - kfree(buf); - if (!zone_blocks) { if (sdkp->first_scan) sd_printk(KERN_NOTICE, sdkp, "Devices with non constant zone " "size are not supported\n"); - return -ENODEV; - } - - if (!is_power_of_2(zone_blocks)) { + ret = -ENODEV; + } else if (!is_power_of_2(zone_blocks)) { if (sdkp->first_scan) sd_printk(KERN_NOTICE, sdkp, "Devices with non power of 2 zone " "size are not supported\n"); - return -ENODEV; - } - - if (logical_to_sectors(sdkp->device, zone_blocks) > UINT_MAX) { + ret = -ENODEV; + } else if (logical_to_sectors(sdkp->device, zone_blocks) > UINT_MAX) { if (sdkp->first_scan) sd_printk(KERN_NOTICE, sdkp, "Zone size too large\n"); - return -ENODEV; + ret = -ENODEV; + } else { + sdkp->zone_blocks = zone_blocks; + sdkp->zone_shift = ilog2(zone_blocks); } - sdkp->zone_blocks = zone_blocks; - sdkp->zone_shift = ilog2(zone_blocks); +out_free: + kfree(buf); - return 0; + return ret; } /**