diff mbox series

[4/5] fs: hfs: initialize fsdata in hfs_file_truncate()

Message ID 20221121112134.407362-4-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/hfs/extent.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Alexander Potapenko Jan. 24, 2023, 10:51 a.m. UTC | #1 
On Mon, Nov 21, 2022 at 12:21 PM Alexander Potapenko <glider@google.com> 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>

Dear FS maintainers,

HFS/HFSPLUS are orphaned, can someone take this patch to their tree?
Thanks in advance!
(same for "fs: hfsplus: initialize fsdata in hfsplus_file_truncate()":
https://lore.kernel.org/all/20221121112134.407362-5-glider@google.com/)
Andrew Morton Jan. 24, 2023, 9:04 p.m. UTC | #2 
On Tue, 24 Jan 2023 11:51:30 +0100 Alexander Potapenko <glider@google.com> wrote:

> On Mon, Nov 21, 2022 at 12:21 PM Alexander Potapenko <glider@google.com> 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>
> 
> Dear FS maintainers,
> 
> HFS/HFSPLUS are orphaned, can someone take this patch to their tree?
> Thanks in advance!
> (same for "fs: hfsplus: initialize fsdata in hfsplus_file_truncate()":
> https://lore.kernel.org/all/20221121112134.407362-5-glider@google.com/)

I grabbed both.

I removed the

	Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")

because that might provoke the backport bots to backport this fix
across eight years worth of kernels.  Before KMSAN existed!

If you intended that this be backported then please let's come up with a
more precise Fixes: target and we'll add cc:stable.
Alexander Potapenko Jan. 25, 2023, 9:51 a.m. UTC | #3 
On Tue, Jan 24, 2023 at 10:04 PM Andrew Morton
<akpm@linux-foundation.org> wrote:
>
> On Tue, 24 Jan 2023 11:51:30 +0100 Alexander Potapenko <glider@google.com> wrote:
>
> > On Mon, Nov 21, 2022 at 12:21 PM Alexander Potapenko <glider@google.com> 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>
> >
> > Dear FS maintainers,
> >
> > HFS/HFSPLUS are orphaned, can someone take this patch to their tree?
> > Thanks in advance!
> > (same for "fs: hfsplus: initialize fsdata in hfsplus_file_truncate()":
> > https://lore.kernel.org/all/20221121112134.407362-5-glider@google.com/)
>
> I grabbed both.
>
> I removed the
>
>         Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
>
> because that might provoke the backport bots to backport this fix
> across eight years worth of kernels.  Before KMSAN existed!

Right, makes sense.
diff mbox series

Patch

diff --git a/fs/hfs/extent.c b/fs/hfs/extent.c
index 3f7e9bef98743..6d1878b99b305 100644
--- a/fs/hfs/extent.c
+++ b/fs/hfs/extent.c
@@ -486,7 +486,7 @@  void hfs_file_truncate(struct inode *inode)
 		inode->i_size);
 	if (inode->i_size > HFS_I(inode)->phys_size) {
 		struct address_space *mapping = inode->i_mapping;
-		void *fsdata;
+		void *fsdata = NULL;
 		struct page *page;
 
 		/* XXX: Can use generic_cont_expand? */