From 63c43b0ec1765b74c734d465ba6345ef4f434df8 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Tue, 15 Dec 2009 17:25:43 +0200 Subject: [PATCH] [SCSI] scsi_lib: Fix bug in completion of bidi commands Because of the terrible structuring of scsi-bidi-commands it breaks some of the life time rules of a scsi-command. It is now not allowed to free up the block-request before cleanup and partial deallocation of the scsi-command. (Which is not so for none bidi commands) The right fix to this problem would be to make bidi command a first citizen by allocating a scsi_sdb pointer at scsi command just like cmd->prot_sdb. The bidi sdb should be allocated/deallocated as part of the get/put_command (Again like the prot_sdb) and the current decoupling of scsi_cmnd and blk-request should be kept. For now make sure scsi_release_buffers() is called before the call to blk_end_request_all() which might cause the suicide of the block requests. At best the leak of bidi buffers, at worse a crash, as there is a race between the existence of the bidi_request and the free of the associated bidi_sdb. The reason this was never hit before is because only OSD has the potential of doing asynchronous bidi commands. (So does bsg but it is never used) And OSD clients just happen to do all their bidi commands synchronously, up until recently. CC: Stable Tree Signed-off-by: Boaz Harrosh Signed-off-by: James Bottomley --- drivers/scsi/scsi_lib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index d8927681ec88..c6642423cc67 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -749,9 +749,9 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) */ req->next_rq->resid_len = scsi_in(cmd)->resid; + scsi_release_buffers(cmd); blk_end_request_all(req, 0); - scsi_release_buffers(cmd); scsi_next_command(cmd); return; } -- 2.30.2