From: Johannes Thumshirn <[email protected]> [ Upstream commit 48ae8484e9fc324b4968d33c585e54bc98e44d61 ]
If the list search in sg_get_rq_mark() fails to find a valid request, we return a bogus element. This then can later lead to a GPF in sg_remove_scat(). So don't return bogus Sg_requests in sg_get_rq_mark() but NULL in case the list search doesn't find a valid request. Signed-off-by: Johannes Thumshirn <[email protected]> Reported-by: Andrey Konovalov <[email protected]> Cc: Hannes Reinecke <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Doug Gilbert <[email protected]> Reviewed-by: Hannes Reinecke <[email protected]> Acked-by: Doug Gilbert <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- drivers/scsi/sg.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 783040af3ead..ddce52b3a87d 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -2118,11 +2118,12 @@ sg_get_rq_mark(Sg_fd * sfp, int pack_id) if ((1 == resp->done) && (!resp->sg_io_owned) && ((-1 == pack_id) || (resp->header.pack_id == pack_id))) { resp->done = 2; /* guard against other readers */ - break; + write_unlock_irqrestore(&sfp->rq_list_lock, iflags); + return resp; } } write_unlock_irqrestore(&sfp->rq_list_lock, iflags); - return resp; + return NULL; } /* always adds to end of list */ -- 2.14.1
