From 22c70d1a9c639b432ffdf083bea44752ad9fc8f3 Mon Sep 17 00:00:00 2001 From: Elena Reshetova Date: Thu, 9 Mar 2017 09:44:02 +0200 Subject: scsi: libfc: convert fc_fcp_pkt.ref_cnt from atomic_t to refcount_t refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Acked-by: Johannes Thumshirn Signed-off-by: Martin K. Petersen --- drivers/scsi/libfc/fc_fcp.c | 6 +++--- include/scsi/libfc.h | 3 ++- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c index 0e67621477a8..a808e8ef1d08 100644 --- a/drivers/scsi/libfc/fc_fcp.c +++ b/drivers/scsi/libfc/fc_fcp.c @@ -154,7 +154,7 @@ static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lport, gfp_t gfp) memset(fsp, 0, sizeof(*fsp)); fsp->lp = lport; fsp->xfer_ddp = FC_XID_UNKNOWN; - atomic_set(&fsp->ref_cnt, 1); + refcount_set(&fsp->ref_cnt, 1); init_timer(&fsp->timer); fsp->timer.data = (unsigned long)fsp; INIT_LIST_HEAD(&fsp->list); @@ -175,7 +175,7 @@ static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lport, gfp_t gfp) */ static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp) { - if (atomic_dec_and_test(&fsp->ref_cnt)) { + if (refcount_dec_and_test(&fsp->ref_cnt)) { struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp); mempool_free(fsp, si->scsi_pkt_pool); @@ -188,7 +188,7 @@ static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp) */ static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp) { - atomic_inc(&fsp->ref_cnt); + refcount_inc(&fsp->ref_cnt); } /** diff --git a/include/scsi/libfc.h b/include/scsi/libfc.h index da5033dd8cbc..2109844be53d 100644 --- a/include/scsi/libfc.h +++ b/include/scsi/libfc.h @@ -23,6 +23,7 @@ #include #include #include +#include #include #include @@ -321,7 +322,7 @@ struct fc_seq_els_data { */ struct fc_fcp_pkt { spinlock_t scsi_pkt_lock; - atomic_t ref_cnt; + refcount_t ref_cnt; /* SCSI command and data transfer information */ u32 data_len; -- cgit v1.2.3