diff options
| author | Steve French <stfrench@microsoft.com> | 2021-07-23 18:35:15 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-08-04 12:46:45 +0200 |
| commit | bfc8e67c60b911ee5605c1234fcb58239e5c20de (patch) | |
| tree | d979cdb27dc734a4dec015ab903ef7f1646cc124 /fs | |
| parent | be561c0154dca82c3e399648bfe1b21b717af144 (diff) | |
SMB3: fix readpage for large swap cache
commit f2a26a3cff27dfa456fef386fe5df56dcb4b47b6 upstream.
readpage was calculating the offset of the page incorrectly
for the case of large swapcaches.
loff_t offset = (loff_t)page->index << PAGE_SHIFT;
As pointed out by Matthew Wilcox, this needs to use
page_file_offset() to calculate the offset instead.
Pages coming from the swap cache have page->index set
to their index within the swapcache, not within the backing
file. For a sufficiently large swapcache, we could have
overlapping values of page->index within the same backing file.
Suggested by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org> # v5.7+
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/cifs/file.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c index da057570bb93..f46904a4ead3 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -4550,7 +4550,7 @@ read_complete: static int cifs_readpage(struct file *file, struct page *page) { - loff_t offset = (loff_t)page->index << PAGE_SHIFT; + loff_t offset = page_file_offset(page); int rc = -EACCES; unsigned int xid; |