fs: ext4: initialize fsdata in pagecache_write()

commit 956510c0c7 upstream.

When aops->write_begin() does not initialize fsdata, KMSAN reports
an error passing the latter to aops->write_end().

Fix this by unconditionally initializing fsdata.

Cc: Eric Biggers <ebiggers@kernel.org>
Fixes: c93d8f8858 ("ext4: add basic fs-verity support")
Reported-by: syzbot+9767be679ef5016b6082@syzkaller.appspotmail.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221121112134.407362-1-glider@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alexander Potapenko 2022-11-21 12:21:30 +01:00 committed by Greg Kroah-Hartman
parent 744bbde378
commit 970bfd7a41
1 changed files with 1 additions and 1 deletions

View File

@ -76,7 +76,7 @@ static int pagecache_write(struct inode *inode, const void *buf, size_t count,
size_t n = min_t(size_t, count,
PAGE_SIZE - offset_in_page(pos));
struct page *page;
void *fsdata;
void *fsdata = NULL;
int res;
res = pagecache_write_begin(NULL, inode->i_mapping, pos, n, 0,