From: Miklos Szeredi <mszeredi@redhat.com> stable inclusion from stable-v5.10.83 commit 8f4d0719f323e84f2ad9ce6b0fc62752abf2bbd4 bugzilla: 185879 https://gitee.com/openeuler/kernel/issues/I4QUVG Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 473441720c8616dfaf4451f9c7ea14f0eb5e5d65 upstream. Checking buf->flags should be done before the pipe_buf_release() is called on the pipe buffer, since releasing the buffer might modify the flags. This is exactly what page_cache_pipe_buf_release() does, and which results in the same VM_BUG_ON_PAGE(PageLRU(page)) that the original patch was trying to fix. Reported-by: Justin Forbes <jmforbes@linuxtx.org> Fixes: 712a951025c0 ("fuse: fix page stealing") Cc: <stable@vger.kernel.org> # v2.6.35 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- fs/fuse/dev.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index fb1917730e0e..d100b5dfedbd 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -851,17 +851,17 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) goto out_put_old; } + get_page(newpage); + + if (!(buf->flags & PIPE_BUF_FLAG_LRU)) + lru_cache_add(newpage); + /* * Release while we have extra ref on stolen page. Otherwise * anon_pipe_buf_release() might think the page can be reused. */ pipe_buf_release(cs->pipe, buf); - get_page(newpage); - - if (!(buf->flags & PIPE_BUF_FLAG_LRU)) - lru_cache_add(newpage); - err = 0; spin_lock(&cs->req->waitq.lock); if (test_bit(FR_ABORTED, &cs->req->flags)) -- 2.20.1