From 8e575c50a171f2579e367a7f778f86477dfdaf49 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Fri, 13 Feb 2015 22:09:47 +0000 Subject: target: Add missing WRITE_SAME end-of-device sanity check This patch adds a check to sbc_setup_write_same() to verify the incoming WRITE_SAME LBA + number of blocks does not exceed past the end-of-device. Also check for potential LBA wrap-around as well. Reported-by: Bart Van Assche Cc: Martin Petersen Cc: Christoph Hellwig Cc: stable@vger.kernel.org # 3.8+ Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_sbc.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/target') diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index 11bea1952435..b26b52f441a1 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -251,6 +251,8 @@ static inline unsigned long long transport_lba_64_ext(unsigned char *cdb) static sense_reason_t sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops) { + struct se_device *dev = cmd->se_dev; + sector_t end_lba = dev->transport->get_blocks(dev) + 1; unsigned int sectors = sbc_get_write_same_sectors(cmd); if ((flags[0] & 0x04) || (flags[0] & 0x02)) { @@ -264,6 +266,16 @@ sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *o sectors, cmd->se_dev->dev_attrib.max_write_same_len); return TCM_INVALID_CDB_FIELD; } + /* + * Sanity check for LBA wrap and request past end of device. + */ + if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) || + ((cmd->t_task_lba + sectors) > end_lba)) { + pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n", + (unsigned long long)end_lba, cmd->t_task_lba, sectors); + return TCM_ADDRESS_OUT_OF_RANGE; + } + /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */ if (flags[0] & 0x10) { pr_warn("WRITE SAME with ANCHOR not supported\n"); -- cgit v1.2.3-59-g8ed1b