From: Johannes Thumshirn <johannes.thumshirn@xxxxxxx> [ Upstream commit 20a66f2bf280277ab5bb22e27445153b4eb0ac88 ] In case scsi_setup_fs_cmnd() fails we're not freeing the sgtables allocated by scsi_init_io(), thus we leak the allocated memory. Free the sgtables allocated by scsi_init_io() in case scsi_setup_fs_cmnd() fails. Technically scsi_setup_scsi_cmnd() does not suffer from this problem as it can only fail if scsi_init_io() fails, so it does not have sgtables allocated. But to maintain symmetry and as a measure of defensive programming, free the sgtables on scsi_setup_scsi_cmnd() failure as well. scsi_mq_free_sgtables() has safeguards against double-freeing of memory so this is safe to do. While we're at it, rename scsi_mq_free_sgtables() to scsi_free_sgtables(). Link: https://bugzilla.kernel.org/show_bug.cgi?id=205595 Link: https://lore.kernel.org/r/20200428104605.8143-2-johannes.thumshirn@xxxxxxx Reviewed-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Daniel Wagner <dwagner@xxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/scsi/scsi_lib.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 06c260f6cdae..3ecdae18597d 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -548,7 +548,7 @@ static void scsi_uninit_cmd(struct scsi_cmnd *cmd) } } -static void scsi_mq_free_sgtables(struct scsi_cmnd *cmd) +static void scsi_free_sgtables(struct scsi_cmnd *cmd) { if (cmd->sdb.table.nents) sg_free_table_chained(&cmd->sdb.table, @@ -560,7 +560,7 @@ static void scsi_mq_free_sgtables(struct scsi_cmnd *cmd) static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd) { - scsi_mq_free_sgtables(cmd); + scsi_free_sgtables(cmd); scsi_uninit_cmd(cmd); } @@ -1059,7 +1059,7 @@ blk_status_t scsi_init_io(struct scsi_cmnd *cmd) return BLK_STS_OK; out_free_sgtables: - scsi_mq_free_sgtables(cmd); + scsi_free_sgtables(cmd); return ret; } EXPORT_SYMBOL(scsi_init_io); @@ -1190,6 +1190,7 @@ static blk_status_t scsi_setup_cmnd(struct scsi_device *sdev, struct request *req) { struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); + blk_status_t ret; if (!blk_rq_bytes(req)) cmd->sc_data_direction = DMA_NONE; @@ -1199,9 +1200,14 @@ static blk_status_t scsi_setup_cmnd(struct scsi_device *sdev, cmd->sc_data_direction = DMA_FROM_DEVICE; if (blk_rq_is_scsi(req)) - return scsi_setup_scsi_cmnd(sdev, req); + ret = scsi_setup_scsi_cmnd(sdev, req); else - return scsi_setup_fs_cmnd(sdev, req); + ret = scsi_setup_fs_cmnd(sdev, req); + + if (ret != BLK_STS_OK) + scsi_free_sgtables(cmd); + + return ret; } static blk_status_t -- 2.25.1
