diff mbox series

[2/5] fs: affs: initialize fsdata in affs_truncate()

Message ID 20221121112134.407362-2-glider@google.com
State New
Headers
Series [1/5] fs: ext4: initialize fsdata in pagecache_write() |

Commit Message

Alexander Potapenko Nov. 21, 2022, 11:21 a.m. UTC 
  When aops->write_begin() does not initialize fsdata, KMSAN may report
an error passing the latter to aops->write_end().

Fix this by unconditionally initializing fsdata.

Suggested-by: Eric Biggers <ebiggers@kernel.org>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Alexander Potapenko <glider@google.com>
---
 fs/affs/file.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Eric Biggers Nov. 21, 2022, 7:46 p.m. UTC | #1 
On Mon, Nov 21, 2022 at 12:21:31PM +0100, Alexander Potapenko wrote:
> When aops->write_begin() does not initialize fsdata, KMSAN may report
> an error passing the latter to aops->write_end().
> 
> Fix this by unconditionally initializing fsdata.
> 
> Suggested-by: Eric Biggers <ebiggers@kernel.org>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")

Are you sure that is the correct Fixes commit?  What about commit f2b6a16eb8f5
("fs: affs convert to new aops")?

- Eric
Alexander Potapenko Nov. 22, 2022, 8:57 a.m. UTC | #2 
On Mon, Nov 21, 2022 at 8:46 PM Eric Biggers <ebiggers@kernel.org> wrote:
>
> On Mon, Nov 21, 2022 at 12:21:31PM +0100, Alexander Potapenko wrote:
> > When aops->write_begin() does not initialize fsdata, KMSAN may report
> > an error passing the latter to aops->write_end().
> >
> > Fix this by unconditionally initializing fsdata.
> >
> > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
>
> Are you sure that is the correct Fixes commit?  What about commit f2b6a16eb8f5
> ("fs: affs convert to new aops")?

Hmm, indeed, you are right.

> - Eric
David Sterba Nov. 22, 2022, 2:56 p.m. UTC | #3 
On Mon, Nov 21, 2022 at 12:21:31PM +0100, Alexander Potapenko wrote:
> When aops->write_begin() does not initialize fsdata, KMSAN may report
> an error passing the latter to aops->write_end().
> 
> Fix this by unconditionally initializing fsdata.
> 
> Suggested-by: Eric Biggers <ebiggers@kernel.org>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Signed-off-by: Alexander Potapenko <glider@google.com>

With the fixed Fixes: reference,

Acked-by: David Sterba <dsterba@suse.com>
Alexander Potapenko Jan. 10, 2023, 12:27 p.m. UTC | #4 
On Tue, Nov 22, 2022 at 3:56 PM David Sterba <dsterba@suse.cz> wrote:
>
> On Mon, Nov 21, 2022 at 12:21:31PM +0100, Alexander Potapenko wrote:
> > When aops->write_begin() does not initialize fsdata, KMSAN may report
> > an error passing the latter to aops->write_end().
> >
> > Fix this by unconditionally initializing fsdata.
> >
> > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> > Signed-off-by: Alexander Potapenko <glider@google.com>
>
> With the fixed Fixes: reference,
>
> Acked-by: David Sterba <dsterba@suse.com>

Hi David,

I've noticed that the ext4 counterpart of this patch is in the
upstream tree already, whereas the affs, f2fs, hfs and hfsplus
versions are not.
Are they picked via a different tree?
David Sterba Jan. 10, 2023, 12:47 p.m. UTC | #5 
On Tue, Jan 10, 2023 at 01:27:03PM +0100, Alexander Potapenko wrote:
> On Tue, Nov 22, 2022 at 3:56 PM David Sterba <dsterba@suse.cz> wrote:
> >
> > On Mon, Nov 21, 2022 at 12:21:31PM +0100, Alexander Potapenko wrote:
> > > When aops->write_begin() does not initialize fsdata, KMSAN may report
> > > an error passing the latter to aops->write_end().
> > >
> > > Fix this by unconditionally initializing fsdata.
> > >
> > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> > > Signed-off-by: Alexander Potapenko <glider@google.com>
> >
> > With the fixed Fixes: reference,
> >
> > Acked-by: David Sterba <dsterba@suse.com>
> 
> Hi David,
> 
> I've noticed that the ext4 counterpart of this patch is in the
> upstream tree already, whereas the affs, f2fs, hfs and hfsplus
> versions are not.
> Are they picked via a different tree?

I thought it would go in with the rest of the series but it seems that
the patches are meant to be merged independently, so I'll do the affs
part.
Eric Biggers Jan. 10, 2023, 6:42 p.m. UTC | #6 
On Tue, Jan 10, 2023 at 01:27:03PM +0100, Alexander Potapenko wrote:
> On Tue, Nov 22, 2022 at 3:56 PM David Sterba <dsterba@suse.cz> wrote:
> >
> > On Mon, Nov 21, 2022 at 12:21:31PM +0100, Alexander Potapenko wrote:
> > > When aops->write_begin() does not initialize fsdata, KMSAN may report
> > > an error passing the latter to aops->write_end().
> > >
> > > Fix this by unconditionally initializing fsdata.
> > >
> > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> > > Signed-off-by: Alexander Potapenko <glider@google.com>
> >
> > With the fixed Fixes: reference,
> >
> > Acked-by: David Sterba <dsterba@suse.com>
> 
> Hi David,
> 
> I've noticed that the ext4 counterpart of this patch is in the
> upstream tree already, whereas the affs, f2fs, hfs and hfsplus
> versions are not.
> Are they picked via a different tree?

Generally each filesystem has its own development tree.  All the information is
in MAINTAINERS.  hfs and hfsplus are unmaintained, though.

Maybe try asking Andrew Morton to apply the hfs and hfsplus patches, and any
others that don't get applied, as "maintainer of last resort".

- Eric
diff mbox series

Patch

diff --git a/fs/affs/file.c b/fs/affs/file.c
index cefa222f7881c..8daeed31e1af9 100644
--- a/fs/affs/file.c
+++ b/fs/affs/file.c
@@ -880,7 +880,7 @@  affs_truncate(struct inode *inode)
 	if (inode->i_size > AFFS_I(inode)->mmu_private) {
 		struct address_space *mapping = inode->i_mapping;
 		struct page *page;
-		void *fsdata;
+		void *fsdata = NULL;
 		loff_t isize = inode->i_size;
 		int res;