Commit 5611ef28 authored Mar 16, 2017 by David Howells

afs: Fix page overput in afs_fill_page()



afs_fill_page() loads the page it wants to fill into the afs_read request
without incrementing its refcount - but then calls afs_put_read() to clean
up afterwards, which then releases a ref on the page.

Fix this by getting a ref on the page before calling
afs_vnode_fetch_data().

This causes sync after a write to hang in afs_writepages_region() because
find_get_pages_tag() gets confused and doesn't return.

Fixes: 196ee9cd ("afs: Make afs_fs_fetch_data() take a list of pages")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>

parent 29c8bbbd

fs/afs/write.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -101,6 +101,7 @@ static int afs_fill_page(struct afs_vnode vnode, struct key key,
		req->pos = pos;
		req->nr_pages = 1;
		req->pages[0] = page;
		get_page(page);

		i_size = i_size_read(&vnode->vfs_inode);
		if (pos + PAGE_SIZE > i_size)

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