<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/fs/fuse, branch v4.14.331</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>fuse: revalidate: don't invalidate if interrupted</title>
<updated>2023-08-11T09:33:47+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@redhat.com</email>
</author>
<published>2023-06-07T15:49:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5f2b320834a2efa56c46a4c07543b93644a92d0e'/>
<id>5f2b320834a2efa56c46a4c07543b93644a92d0e</id>
<content type='text'>
commit a9d1c4c6df0e568207907c04aed9e7beb1294c42 upstream.

If the LOOKUP request triggered from fuse_dentry_revalidate() is
interrupted, then the dentry will be invalidated, possibly resulting in
submounts being unmounted.

Reported-by: Xu Rongbo &lt;xurongbo@baidu.com&gt;
Closes: https://lore.kernel.org/all/CAJfpegswN_CJJ6C3RZiaK6rpFmNyWmXfaEpnQUJ42KCwNF5tWw@mail.gmail.com/
Fixes: 9e6268db496a ("[PATCH] FUSE - read-write operations")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a9d1c4c6df0e568207907c04aed9e7beb1294c42 upstream.

If the LOOKUP request triggered from fuse_dentry_revalidate() is
interrupted, then the dentry will be invalidated, possibly resulting in
submounts being unmounted.

Reported-by: Xu Rongbo &lt;xurongbo@baidu.com&gt;
Closes: https://lore.kernel.org/all/CAJfpegswN_CJJ6C3RZiaK6rpFmNyWmXfaEpnQUJ42KCwNF5tWw@mail.gmail.com/
Fixes: 9e6268db496a ("[PATCH] FUSE - read-write operations")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: Remove uninitialized_var() usage</title>
<updated>2023-08-11T09:33:32+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2020-06-03T20:09:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d68627697d173a236b9b8468ed5d928cab7a7d61'/>
<id>d68627697d173a236b9b8468ed5d928cab7a7d61</id>
<content type='text'>
commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream.

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky &lt;leonro@mellanox.com&gt; # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt; # IB
Acked-by: Kalle Valo &lt;kvalo@codeaurora.org&gt; # wireless drivers
Reviewed-by: Chao Yu &lt;yuchao0@huawei.com&gt; # erofs
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream.

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky &lt;leonro@mellanox.com&gt; # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt; # IB
Acked-by: Kalle Valo &lt;kvalo@codeaurora.org&gt; # wireless drivers
Reviewed-by: Chao Yu &lt;yuchao0@huawei.com&gt; # erofs
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fuse: limit nsec</title>
<updated>2022-08-25T09:11:12+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@redhat.com</email>
</author>
<published>2022-07-21T14:06:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f41d1503642e7632b2d65fe5d2cea95371e4069f'/>
<id>f41d1503642e7632b2d65fe5d2cea95371e4069f</id>
<content type='text'>
commit 47912eaa061a6a81e4aa790591a1874c650733c0 upstream.

Limit nanoseconds to 0..999999999.

Fixes: d8a5ba45457e ("[PATCH] FUSE - core")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 47912eaa061a6a81e4aa790591a1874c650733c0 upstream.

Limit nanoseconds to 0..999999999.

Fixes: d8a5ba45457e ("[PATCH] FUSE - core")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fuse: fix pipe buffer lifetime for direct_io</title>
<updated>2022-04-20T07:08:08+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@redhat.com</email>
</author>
<published>2022-03-07T15:30:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0ab55e14cf5fd40c39109969c8b04a25870f5d1e'/>
<id>0ab55e14cf5fd40c39109969c8b04a25870f5d1e</id>
<content type='text'>
commit 0c4bcfdecb1ac0967619ee7ff44871d93c08c909 upstream.

In FOPEN_DIRECT_IO mode, fuse_file_write_iter() calls
fuse_direct_write_iter(), which normally calls fuse_direct_io(), which then
imports the write buffer with fuse_get_user_pages(), which uses
iov_iter_get_pages() to grab references to userspace pages instead of
actually copying memory.

On the filesystem device side, these pages can then either be read to
userspace (via fuse_dev_read()), or splice()d over into a pipe using
fuse_dev_splice_read() as pipe buffers with &amp;nosteal_pipe_buf_ops.

This is wrong because after fuse_dev_do_read() unlocks the FUSE request,
the userspace filesystem can mark the request as completed, causing write()
to return. At that point, the userspace filesystem should no longer have
access to the pipe buffer.

Fix by copying pages coming from the user address space to new pipe
buffers.

Reported-by: Jann Horn &lt;jannh@google.com&gt;
Fixes: c3021629a0d8 ("fuse: support splice() reading from fuse device")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Zach O'Keefe &lt;zokeefe@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0c4bcfdecb1ac0967619ee7ff44871d93c08c909 upstream.

In FOPEN_DIRECT_IO mode, fuse_file_write_iter() calls
fuse_direct_write_iter(), which normally calls fuse_direct_io(), which then
imports the write buffer with fuse_get_user_pages(), which uses
iov_iter_get_pages() to grab references to userspace pages instead of
actually copying memory.

On the filesystem device side, these pages can then either be read to
userspace (via fuse_dev_read()), or splice()d over into a pipe using
fuse_dev_splice_read() as pipe buffers with &amp;nosteal_pipe_buf_ops.

This is wrong because after fuse_dev_do_read() unlocks the FUSE request,
the userspace filesystem can mark the request as completed, causing write()
to return. At that point, the userspace filesystem should no longer have
access to the pipe buffer.

Fix by copying pages coming from the user address space to new pipe
buffers.

Reported-by: Jann Horn &lt;jannh@google.com&gt;
Fixes: c3021629a0d8 ("fuse: support splice() reading from fuse device")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Zach O'Keefe &lt;zokeefe@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fuse: fix live lock in fuse_iget()</title>
<updated>2022-01-27T08:01:02+00:00</updated>
<author>
<name>Amir Goldstein</name>
<email>amir73il@gmail.com</email>
</author>
<published>2022-01-24T15:18:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f78d626801194ffac2c140de72e5b7937fac33f6'/>
<id>f78d626801194ffac2c140de72e5b7937fac33f6</id>
<content type='text'>
commit 775c5033a0d164622d9d10dd0f0a5531639ed3ed upstream.

Commit 5d069dbe8aaf ("fuse: fix bad inode") replaced make_bad_inode()
in fuse_iget() with a private implementation fuse_make_bad().

The private implementation fails to remove the bad inode from inode
cache, so the retry loop with iget5_locked() finds the same bad inode
and marks it bad forever.

kmsg snip:

[ ] rcu: INFO: rcu_sched self-detected stall on CPU
...
[ ]  ? bit_wait_io+0x50/0x50
[ ]  ? fuse_init_file_inode+0x70/0x70
[ ]  ? find_inode.isra.32+0x60/0xb0
[ ]  ? fuse_init_file_inode+0x70/0x70
[ ]  ilookup5_nowait+0x65/0x90
[ ]  ? fuse_init_file_inode+0x70/0x70
[ ]  ilookup5.part.36+0x2e/0x80
[ ]  ? fuse_init_file_inode+0x70/0x70
[ ]  ? fuse_inode_eq+0x20/0x20
[ ]  iget5_locked+0x21/0x80
[ ]  ? fuse_inode_eq+0x20/0x20
[ ]  fuse_iget+0x96/0x1b0

Fixes: 5d069dbe8aaf ("fuse: fix bad inode")
Signed-off-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 775c5033a0d164622d9d10dd0f0a5531639ed3ed upstream.

Commit 5d069dbe8aaf ("fuse: fix bad inode") replaced make_bad_inode()
in fuse_iget() with a private implementation fuse_make_bad().

The private implementation fails to remove the bad inode from inode
cache, so the retry loop with iget5_locked() finds the same bad inode
and marks it bad forever.

kmsg snip:

[ ] rcu: INFO: rcu_sched self-detected stall on CPU
...
[ ]  ? bit_wait_io+0x50/0x50
[ ]  ? fuse_init_file_inode+0x70/0x70
[ ]  ? find_inode.isra.32+0x60/0xb0
[ ]  ? fuse_init_file_inode+0x70/0x70
[ ]  ilookup5_nowait+0x65/0x90
[ ]  ? fuse_init_file_inode+0x70/0x70
[ ]  ilookup5.part.36+0x2e/0x80
[ ]  ? fuse_init_file_inode+0x70/0x70
[ ]  ? fuse_inode_eq+0x20/0x20
[ ]  iget5_locked+0x21/0x80
[ ]  ? fuse_inode_eq+0x20/0x20
[ ]  fuse_iget+0x96/0x1b0

Fixes: 5d069dbe8aaf ("fuse: fix bad inode")
Signed-off-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fuse: fix bad inode</title>
<updated>2022-01-27T08:01:01+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@redhat.com</email>
</author>
<published>2022-01-24T15:17:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2cd45139c0f28ebfa7604866faee00c99231a62b'/>
<id>2cd45139c0f28ebfa7604866faee00c99231a62b</id>
<content type='text'>
commit 5d069dbe8aaf2a197142558b6fb2978189ba3454 upstream.

Jan Kara's analysis of the syzbot report (edited):

  The reproducer opens a directory on FUSE filesystem, it then attaches
  dnotify mark to the open directory.  After that a fuse_do_getattr() call
  finds that attributes returned by the server are inconsistent, and calls
  make_bad_inode() which, among other things does:

          inode-&gt;i_mode = S_IFREG;

  This then confuses dnotify which doesn't tear down its structures
  properly and eventually crashes.

Avoid calling make_bad_inode() on a live inode: switch to a private flag on
the fuse inode.  Also add the test to ops which the bad_inode_ops would
have caught.

This bug goes back to the initial merge of fuse in 2.6.14...

Reported-by: syzbot+f427adf9324b92652ccc@syzkaller.appspotmail.com
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Tested-by: Jan Kara &lt;jack@suse.cz&gt;
Cc: &lt;stable@vger.kernel.org&gt;
[bwh: Backported to 4.19:
 - Drop changes in fuse_dir_fsync(), fuse_readahead(), fuse_evict_inode()
 - In fuse_get_link(), return ERR_PTR(-EIO) for bad inodes
 - Convert some additional calls to is_bad_inode()
 - Adjust filename, context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5d069dbe8aaf2a197142558b6fb2978189ba3454 upstream.

Jan Kara's analysis of the syzbot report (edited):

  The reproducer opens a directory on FUSE filesystem, it then attaches
  dnotify mark to the open directory.  After that a fuse_do_getattr() call
  finds that attributes returned by the server are inconsistent, and calls
  make_bad_inode() which, among other things does:

          inode-&gt;i_mode = S_IFREG;

  This then confuses dnotify which doesn't tear down its structures
  properly and eventually crashes.

Avoid calling make_bad_inode() on a live inode: switch to a private flag on
the fuse inode.  Also add the test to ops which the bad_inode_ops would
have caught.

This bug goes back to the initial merge of fuse in 2.6.14...

Reported-by: syzbot+f427adf9324b92652ccc@syzkaller.appspotmail.com
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Tested-by: Jan Kara &lt;jack@suse.cz&gt;
Cc: &lt;stable@vger.kernel.org&gt;
[bwh: Backported to 4.19:
 - Drop changes in fuse_dir_fsync(), fuse_readahead(), fuse_evict_inode()
 - In fuse_get_link(), return ERR_PTR(-EIO) for bad inodes
 - Convert some additional calls to is_bad_inode()
 - Adjust filename, context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fuse: annotate lock in fuse_reverse_inval_entry()</title>
<updated>2021-12-22T08:18:01+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@redhat.com</email>
</author>
<published>2021-10-22T15:03:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e5751a4cdee1fb8b6ec6c6f5f6f4fee210d3c1b9'/>
<id>e5751a4cdee1fb8b6ec6c6f5f6f4fee210d3c1b9</id>
<content type='text'>
commit bda9a71980e083699a0360963c0135657b73f47a upstream.

Add missing inode lock annotatation; found by syzbot.

Reported-and-tested-by: syzbot+9f747458f5990eaa8d43@syzkaller.appspotmail.com
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit bda9a71980e083699a0360963c0135657b73f47a upstream.

Add missing inode lock annotatation; found by syzbot.

Reported-and-tested-by: syzbot+9f747458f5990eaa8d43@syzkaller.appspotmail.com
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fuse: release pipe buf after last use</title>
<updated>2021-12-08T07:46:52+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@redhat.com</email>
</author>
<published>2021-11-25T13:05:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=89f4bb06cdeab8e503812170524099e5e48b2998'/>
<id>89f4bb06cdeab8e503812170524099e5e48b2998</id>
<content type='text'>
commit 473441720c8616dfaf4451f9c7ea14f0eb5e5d65 upstream.

Checking buf-&gt;flags should be done before the pipe_buf_release() is called
on the pipe buffer, since releasing the buffer might modify the flags.

This is exactly what page_cache_pipe_buf_release() does, and which results
in the same VM_BUG_ON_PAGE(PageLRU(page)) that the original patch was
trying to fix.

Reported-by: Justin Forbes &lt;jmforbes@linuxtx.org&gt;
Fixes: 712a951025c0 ("fuse: fix page stealing")
Cc: &lt;stable@vger.kernel.org&gt; # v2.6.35
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 473441720c8616dfaf4451f9c7ea14f0eb5e5d65 upstream.

Checking buf-&gt;flags should be done before the pipe_buf_release() is called
on the pipe buffer, since releasing the buffer might modify the flags.

This is exactly what page_cache_pipe_buf_release() does, and which results
in the same VM_BUG_ON_PAGE(PageLRU(page)) that the original patch was
trying to fix.

Reported-by: Justin Forbes &lt;jmforbes@linuxtx.org&gt;
Fixes: 712a951025c0 ("fuse: fix page stealing")
Cc: &lt;stable@vger.kernel.org&gt; # v2.6.35
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>fuse: fix page stealing</title>
<updated>2021-12-08T07:46:48+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@redhat.com</email>
</author>
<published>2021-11-02T10:10:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=017fc242d6ce52e16e00ffdfddf95ed75316d678'/>
<id>017fc242d6ce52e16e00ffdfddf95ed75316d678</id>
<content type='text'>
commit 712a951025c0667ff00b25afc360f74e639dfabe upstream.

It is possible to trigger a crash by splicing anon pipe bufs to the fuse
device.

The reason for this is that anon_pipe_buf_release() will reuse buf-&gt;page if
the refcount is 1, but that page might have already been stolen and its
flags modified (e.g. PG_lru added).

This happens in the unlikely case of fuse_dev_splice_write() getting around
to calling pipe_buf_release() after a page has been stolen, added to the
page cache and removed from the page cache.

Fix by calling pipe_buf_release() right after the page was inserted into
the page cache.  In this case the page has an elevated refcount so any
release function will know that the page isn't reusable.

Reported-by: Frank Dinoff &lt;fdinoff@google.com&gt;
Link: https://lore.kernel.org/r/CAAmZXrsGg2xsP1CK+cbuEMumtrqdvD-NKnWzhNcvn71RV3c1yw@mail.gmail.com/
Fixes: dd3bb14f44a6 ("fuse: support splice() writing to fuse device")
Cc: &lt;stable@vger.kernel.org&gt; # v2.6.35
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
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<pre>
commit 712a951025c0667ff00b25afc360f74e639dfabe upstream.

It is possible to trigger a crash by splicing anon pipe bufs to the fuse
device.

The reason for this is that anon_pipe_buf_release() will reuse buf-&gt;page if
the refcount is 1, but that page might have already been stolen and its
flags modified (e.g. PG_lru added).

This happens in the unlikely case of fuse_dev_splice_write() getting around
to calling pipe_buf_release() after a page has been stolen, added to the
page cache and removed from the page cache.

Fix by calling pipe_buf_release() right after the page was inserted into
the page cache.  In this case the page has an elevated refcount so any
release function will know that the page isn't reusable.

Reported-by: Frank Dinoff &lt;fdinoff@google.com&gt;
Link: https://lore.kernel.org/r/CAAmZXrsGg2xsP1CK+cbuEMumtrqdvD-NKnWzhNcvn71RV3c1yw@mail.gmail.com/
Fixes: dd3bb14f44a6 ("fuse: support splice() writing to fuse device")
Cc: &lt;stable@vger.kernel.org&gt; # v2.6.35
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fuse: reject internal errno</title>
<updated>2021-07-20T14:17:45+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@redhat.com</email>
</author>
<published>2021-06-22T07:15:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d172a77a790c1b755eed952ae0745c00c6fe3408'/>
<id>d172a77a790c1b755eed952ae0745c00c6fe3408</id>
<content type='text'>
commit 49221cf86d18bb66fe95d3338cb33bd4b9880ca5 upstream.

Don't allow userspace to report errors that could be kernel-internal.

Reported-by: Anatoly Trosinenko &lt;anatoly.trosinenko@gmail.com&gt;
Fixes: 334f485df85a ("[PATCH] FUSE - device functions")
Cc: &lt;stable@vger.kernel.org&gt; # v2.6.14
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
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<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 49221cf86d18bb66fe95d3338cb33bd4b9880ca5 upstream.

Don't allow userspace to report errors that could be kernel-internal.

Reported-by: Anatoly Trosinenko &lt;anatoly.trosinenko@gmail.com&gt;
Fixes: 334f485df85a ("[PATCH] FUSE - device functions")
Cc: &lt;stable@vger.kernel.org&gt; # v2.6.14
Signed-off-by: Miklos Szeredi &lt;mszeredi@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
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