diff options
author | Elena Reshetova <elena.reshetova@intel.com> | 2017-03-06 16:21:11 +0200 |
---|---|---|
committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2017-05-01 22:20:43 -0700 |
commit | 5981c245a890db6a6e16fb6d3838cc9fc9fdf0ff (patch) | |
tree | a1aa3f65fa046e1ac40b923e97b8b2f36b347c08 | |
parent | a5d68ba85801a78c892a0eb8efb711e293ed314b (diff) | |
download | lwn-5981c245a890db6a6e16fb6d3838cc9fc9fdf0ff.tar.gz lwn-5981c245a890db6a6e16fb6d3838cc9fc9fdf0ff.zip |
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>
-rw-r--r-- | drivers/target/target_core_iblock.c | 12 | ||||
-rw-r--r-- | drivers/target/target_core_iblock.h | 3 |
2 files changed, 8 insertions, 7 deletions
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c index d316ed537d59..bb069ebe4aa6 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++; } diff --git a/drivers/target/target_core_iblock.h b/drivers/target/target_core_iblock.h index 718d3fcd3e7c..f2a5797217d4 100644 --- a/drivers/target/target_core_iblock.h +++ b/drivers/target/target_core_iblock.h @@ -2,6 +2,7 @@ #define TARGET_CORE_IBLOCK_H #include <linux/atomic.h> +#include <linux/refcount.h> #include <target/target_core_base.h> #define IBLOCK_VERSION "4.0" @@ -10,7 +11,7 @@ #define IBLOCK_LBA_SHIFT 9 struct iblock_req { - atomic_t pending; + refcount_t pending; atomic_t ib_bio_err_cnt; } ____cacheline_aligned; |