diff options
author | Christoph Hellwig <hch@lst.de> | 2014-04-15 12:24:55 +0200 |
---|---|---|
committer | James Bottomley <JBottomley@Parallels.com> | 2014-04-21 07:57:21 -0700 |
commit | 5e012aad85f2ee31d7de5c21d63ccd2702d63db2 (patch) | |
tree | fa90a6a3e94a5c3112b3bbdf114c637aa7166eba | |
parent | 67c99a72e3006e4276e91d7282a3d6734fc77a0b (diff) |
[SCSI] don't reference freed command in scsi_init_sgtable
Patch
commit 0479633686d370303e3430256ace4bd5f7f138dc
Author: Christoph Hellwig <hch@infradead.org>
Date: Thu Feb 20 14:20:55 2014 -0800
[SCSI] do not manipulate device reference counts in scsi_get/put_command
Introduced a use after free: when scsi_init_io fails we have to release our
device reference, but we do this trying to reference the just freed command.
Add a local scsi_device pointer to fix this.
Fixes: 0479633686d370303e3430256ace4bd5f7f138dc
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
-rw-r--r-- | drivers/scsi/scsi_lib.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 65a123d9c676..54eff6a79fb8 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1044,6 +1044,7 @@ static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb, */ int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask) { + struct scsi_device *sdev = cmd->device; struct request *rq = cmd->request; int error = scsi_init_sgtable(rq, &cmd->sdb, gfp_mask); @@ -1091,7 +1092,7 @@ err_exit: scsi_release_buffers(cmd); cmd->request->special = NULL; scsi_put_command(cmd); - put_device(&cmd->device->sdev_gendev); + put_device(&sdev->sdev_gendev); return error; } EXPORT_SYMBOL(scsi_init_io); |