diff options
| author | Elena Reshetova <elena.reshetova@intel.com> | 2017-03-03 10:55:23 +0200 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2017-04-18 14:07:24 +0200 |
| commit | 186debd6ede29da9d51cffdb93cadee66e4e1e23 (patch) | |
| tree | 76a630c3cb8e25d593fc59d70175d9ada2b25e01 /fs/btrfs/scrub.c | |
| parent | 6f615018b35fb5ea1ce49673079fc637a0b6be70 (diff) | |
| download | lwn-186debd6ede29da9d51cffdb93cadee66e4e1e23.tar.gz lwn-186debd6ede29da9d51cffdb93cadee66e4e1e23.zip | |
btrfs: convert scrub_block.refs 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: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/scrub.c')
| -rw-r--r-- | fs/btrfs/scrub.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index c9406bf302b8..d2c35848e61d 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -112,7 +112,7 @@ struct scrub_block { struct scrub_page *pagev[SCRUB_MAX_PAGES_PER_BLOCK]; int page_count; atomic_t outstanding_pages; - atomic_t refs; /* free mem on transition to zero */ + refcount_t refs; /* free mem on transition to zero */ struct scrub_ctx *sctx; struct scrub_parity *sparity; struct { @@ -1998,12 +1998,12 @@ static int scrub_checksum_super(struct scrub_block *sblock) static void scrub_block_get(struct scrub_block *sblock) { - atomic_inc(&sblock->refs); + refcount_inc(&sblock->refs); } static void scrub_block_put(struct scrub_block *sblock) { - if (atomic_dec_and_test(&sblock->refs)) { + if (refcount_dec_and_test(&sblock->refs)) { int i; if (sblock->sparity) @@ -2255,7 +2255,7 @@ static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len, /* one ref inside this function, plus one for each page added to * a bio later on */ - atomic_set(&sblock->refs, 1); + refcount_set(&sblock->refs, 1); sblock->sctx = sctx; sblock->no_io_error_seen = 1; @@ -2555,7 +2555,7 @@ static int scrub_pages_for_parity(struct scrub_parity *sparity, /* one ref inside this function, plus one for each page added to * a bio later on */ - atomic_set(&sblock->refs, 1); + refcount_set(&sblock->refs, 1); sblock->sctx = sctx; sblock->no_io_error_seen = 1; sblock->sparity = sparity; |