+ fs-cramfs-inodec-initialize-file_ra_state.patch added to mm-hotfixes-unstable branch

+ fs-cramfs-inodec-initialize-file_ra_state.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: fs/cramfs/inode.c: initialize file_ra_state
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     fs-cramfs-inodec-initialize-file_ra_state.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/fs-cramfs-inodec-initialize-file_ra_state.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: fs/cramfs/inode.c: initialize file_ra_state
Date: Sun Feb 26 12:31:11 PM PST 2023

file_ra_state_init() assumes that the file_ra_state has been zeroed out. 
Fixes a KMSAN used-unintialized issue (at least).

Fixes: cf948cbc35e80 ("cramfs: read_mapping_page() is synchronous")
Reported-by: syzbot <syzbot+8ce7f8308d91e6b8bbe2@syzkaller.appspotmail.com>
  Link: https://lkml.kernel.org/r/0000000000008f74e905f56df987@google.com
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---


--- a/fs/cramfs/inode.c~fs-cramfs-inodec-initialize-file_ra_state
+++ b/fs/cramfs/inode.c
@@ -183,7 +183,7 @@ static void *cramfs_blkdev_read(struct super_block *sb, unsigned int offset,
 				unsigned int len)
 {
 	struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
-	struct file_ra_state ra;
+	struct file_ra_state ra = {};
 	struct page *pages[BLKS_PER_BUF];
 	unsigned i, blocknr, buffer;
 	unsigned long devsize;
_

Patches currently in -mm which might be from akpm@linux-foundation.org are

fs-cramfs-inodec-initialize-file_ra_state.patch
mm-page_alloc-reduce-page-alloc-free-sanity-checks-checkpatch-fixes.patch
mm-page_alloc-reduce-page-alloc-free-sanity-checks-fix.patch
mm-userfaultfd-support-wp-on-multiple-vmas-fix.patch