Messages in this thread Patch in this message | | | Date | Wed, 17 Jun 2015 01:04:31 +0200 | From | Oleg Nesterov <> | Subject | [PATCH 3/3] aio_free_ring: don't do page_count(NULL) |
| |
aio_free_ring() can actually see the NULL page in ->ring_pages[], this can happen if aio_setup_ring() fails.
And in this case page_count(ctx->ring_pages[i]) can OOPS.
Signed-off-by: Oleg Nesterov <oleg@redhat.com> --- fs/aio.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/fs/aio.c b/fs/aio.c index b605ab2..666fbb8 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -292,12 +292,12 @@ static void aio_free_ring(struct kioctx *ctx) put_aio_ring_file(ctx); for (i = 0; i < ctx->nr_pages; i++) { - struct page *page; - pr_debug("pid(%d) [%d] page->count=%d\n", current->pid, i, - page_count(ctx->ring_pages[i])); - page = ctx->ring_pages[i]; + struct page *page = ctx->ring_pages[i]; if (!page) continue; + + pr_debug("pid(%d) [%d] page->count=%d\n", + current->pid, i, page_count(page)); ctx->ring_pages[i] = NULL; put_page(page); } -- 1.5.5.1
| |