target/iblock: convert iblock_req.pending 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 <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index d316ed5..bb069eb 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -279,7 +279,7 @@ static void iblock_complete_cmd(struct se_cmd *cmd)
struct iblock_req *ibr = cmd->priv;
u8 status;
- if (!atomic_dec_and_test(&ibr->pending))
+ if (!refcount_dec_and_test(&ibr->pending))
return;
if (atomic_read(&ibr->ib_bio_err_cnt))
@@ -487,7 +487,7 @@ iblock_execute_write_same(struct se_cmd *cmd)
bio_list_init(&list);
bio_list_add(&list, bio);
- atomic_set(&ibr->pending, 1);
+ refcount_set(&ibr->pending, 1);
while (sectors) {
while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
@@ -498,7 +498,7 @@ iblock_execute_write_same(struct se_cmd *cmd)
if (!bio)
goto fail_put_bios;
- atomic_inc(&ibr->pending);
+ refcount_inc(&ibr->pending);
bio_list_add(&list, bio);
}
@@ -706,7 +706,7 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
cmd->priv = ibr;
if (!sgl_nents) {
- atomic_set(&ibr->pending, 1);
+ refcount_set(&ibr->pending, 1);
iblock_complete_cmd(cmd);
return 0;
}
@@ -719,7 +719,7 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
bio_list_init(&list);
bio_list_add(&list, bio);
- atomic_set(&ibr->pending, 2);
+ refcount_set(&ibr->pending, 2);
bio_cnt = 1;
for_each_sg(sgl, sg, sgl_nents, i) {
@@ -740,7 +740,7 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
if (!bio)
goto fail_put_bios;
- atomic_inc(&ibr->pending);
+ refcount_inc(&ibr->pending);
bio_list_add(&list, bio);
bio_cnt++;
}
