From: Nicholas Bellinger <[email protected]> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== commit 8e575c50a171f2579e367a7f778f86477dfdaf49 upstream. 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 <[email protected]> Cc: Martin Petersen <[email protected]> Cc: Christoph Hellwig <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> --- drivers/target/target_core_sbc.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index d83aea80d83c..42efb40ac596 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -250,6 +250,8 @@ 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)) { @@ -263,6 +265,16 @@ 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"); -- 2.3.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
