From: Andreas Gruenbacher <agruenba@redhat.com> stable inclusion from stable-5.10.50 commit 3ae1c663bdeb4cb82c557478358527ddacd516d8 bugzilla: 174522 https://gitee.com/openeuler/kernel/issues/I4DNFY Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit d3c51c55cb9274dd43c156f1f26b5eb4d5f2d58c upstream. On filesystems with a block size smaller than PAGE_SIZE and non-empty files smaller then PAGE_SIZE, gfs2_page_mkwrite could end up allocating excess blocks beyond the end of the file, similar to fallocate. This doesn't make sense; fix it. Reported-by: Bob Peterson <rpeterso@redhat.com> Fixes: 184b4e60853d ("gfs2: Fix end-of-file handling in gfs2_page_mkwrite") Cc: stable@vger.kernel.org # v5.5+ Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- fs/gfs2/file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 16fb0184ce5e..cfd9d03f604f 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -474,8 +474,8 @@ static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf) file_update_time(vmf->vma->vm_file); /* page is wholly or partially inside EOF */ - if (offset > size - PAGE_SIZE) - length = offset_in_page(size); + if (size - offset < PAGE_SIZE) + length = size - offset; else length = PAGE_SIZE; -- 2.20.1