From: David Howells dhowells@redhat.com
stable inclusion from stable-v5.10.106 commit 2039900aadba14f438b04d262721ffebc4d33547 bugzilla: https://gitee.com/openeuler/kernel/issues/I573US
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit c1853fbadcba1497f4907971e7107888e0714c81 upstream.
When a pipe ring descriptor points to a notification message, the refcount on the backing page is incremented by the generic get function, but the release function, which marks the bitmap, doesn't drop the page ref.
Fix this by calling generic_pipe_buf_release() at the end of watch_queue_pipe_buf_release().
Fixes: c73be61cede5 ("pipe: Add general notification queue support") Reported-by: Jann Horn jannh@google.com Signed-off-by: David Howells dhowells@redhat.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yu Liao liaoyu15@huawei.com Reviewed-by: Wei Li liwei391@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- kernel/watch_queue.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/kernel/watch_queue.c b/kernel/watch_queue.c index 0ef8f65bd2d7..6ddd860d35ce 100644 --- a/kernel/watch_queue.c +++ b/kernel/watch_queue.c @@ -54,6 +54,7 @@ static void watch_queue_pipe_buf_release(struct pipe_inode_info *pipe, bit += page->index;
set_bit(bit, wqueue->notes_bitmap); + generic_pipe_buf_release(pipe, buf); }
// No try_steal function => no stealing