| Message ID | 1334918836-7341-1-git-send-email-stefan.bader@canonical.com |
|---|---|
| State | New |
| Headers | show |
On 04/20/2012 03:47 AM, Stefan Bader wrote: > local dos because of journal_unmap_buffer() > > This is pending in Oneiric but can be cherry-picked all the way > back into Hardy. Proposing for Hardy, Lucid, Natty, Natty/ti-omap4. > > -Stefan > > From 15291164b22a357cb211b618adfef4fa82fc0de3 Mon Sep 17 00:00:00 2001 > From: Eric Sandeen<sandeen@redhat.com> > Date: Mon, 20 Feb 2012 17:53:01 -0500 > Subject: [PATCH] jbd2: clear BH_Delay& BH_Unwritten in journal_unmap_buffer > > journal_unmap_buffer()'s zap_buffer: code clears a lot of buffer head > state ala discard_buffer(), but does not touch _Delay or _Unwritten as > discard_buffer() does. > > This can be problematic in some areas of the ext4 code which assume > that if they have found a buffer marked unwritten or delay, then it's > a live one. Perhaps those spots should check whether it is mapped > as well, but if jbd2 is going to tear down a buffer, let's really > tear it down completely. > > Without this I get some fsx failures on sub-page-block filesystems > up until v3.2, at which point 4e96b2dbbf1d7e81f22047a50f862555a6cb87cb > and 189e868fa8fdca702eb9db9d8afc46b5cb9144c9 make the failures go > away, because buried within that large change is some more flag > clearing. I still think it's worth doing in jbd2, since > ->invalidatepage leads here directly, and it's the right place > to clear away these flags. > > Signed-off-by: Eric Sandeen<sandeen@redhat.com> > Signed-off-by: "Theodore Ts'o"<tytso@mit.edu> > Cc: stable@vger.kernel.org > > BugLink: http://bugs.launchpad.net/bugs/929781 > CVE-2011-4086 > > (cherry-picked from 15291164b22a357cb211b618adfef4fa82fc0de3 upstream) > Signed-off-by: Stefan Bader<stefan.bader@canonical.com> Acked-by: Leann Ogasawara <leann.ogasawara@canonical.com> > --- > fs/jbd2/transaction.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c > index 35ae096..52653306 100644 > --- a/fs/jbd2/transaction.c > +++ b/fs/jbd2/transaction.c > @@ -1949,6 +1949,8 @@ zap_buffer_unlocked: > clear_buffer_mapped(bh); > clear_buffer_req(bh); > clear_buffer_new(bh); > + clear_buffer_delay(bh); > + clear_buffer_unwritten(bh); > bh->b_bdev = NULL; > return may_free; > }
On Fri, Apr 20, 2012 at 12:47:16PM +0200, Stefan Bader wrote: > local dos because of journal_unmap_buffer() > > This is pending in Oneiric but can be cherry-picked all the way > back into Hardy. Proposing for Hardy, Lucid, Natty, Natty/ti-omap4. > > -Stefan > > From 15291164b22a357cb211b618adfef4fa82fc0de3 Mon Sep 17 00:00:00 2001 > From: Eric Sandeen <sandeen@redhat.com> > Date: Mon, 20 Feb 2012 17:53:01 -0500 > Subject: [PATCH] jbd2: clear BH_Delay & BH_Unwritten in journal_unmap_buffer > > journal_unmap_buffer()'s zap_buffer: code clears a lot of buffer head > state ala discard_buffer(), but does not touch _Delay or _Unwritten as > discard_buffer() does. > > This can be problematic in some areas of the ext4 code which assume > that if they have found a buffer marked unwritten or delay, then it's > a live one. Perhaps those spots should check whether it is mapped > as well, but if jbd2 is going to tear down a buffer, let's really > tear it down completely. > > Without this I get some fsx failures on sub-page-block filesystems > up until v3.2, at which point 4e96b2dbbf1d7e81f22047a50f862555a6cb87cb > and 189e868fa8fdca702eb9db9d8afc46b5cb9144c9 make the failures go > away, because buried within that large change is some more flag > clearing. I still think it's worth doing in jbd2, since > ->invalidatepage leads here directly, and it's the right place > to clear away these flags. > > Signed-off-by: Eric Sandeen <sandeen@redhat.com> > Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> > Cc: stable@vger.kernel.org > > BugLink: http://bugs.launchpad.net/bugs/929781 > CVE-2011-4086 > > (cherry-picked from 15291164b22a357cb211b618adfef4fa82fc0de3 upstream) > Signed-off-by: Stefan Bader <stefan.bader@canonical.com> > --- > fs/jbd2/transaction.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c > index 35ae096..52653306 100644 > --- a/fs/jbd2/transaction.c > +++ b/fs/jbd2/transaction.c > @@ -1949,6 +1949,8 @@ zap_buffer_unlocked: > clear_buffer_mapped(bh); > clear_buffer_req(bh); > clear_buffer_new(bh); > + clear_buffer_delay(bh); > + clear_buffer_unwritten(bh); > bh->b_bdev = NULL; > return may_free; > } > -- > 1.7.9.5 > > > -- > kernel-team mailing list > kernel-team@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/kernel-team >
Applied and pushed to Natty master-next and ti-omap4, Lucid and Hardy
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index 35ae096..52653306 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -1949,6 +1949,8 @@ zap_buffer_unlocked: clear_buffer_mapped(bh); clear_buffer_req(bh); clear_buffer_new(bh); + clear_buffer_delay(bh); + clear_buffer_unwritten(bh); bh->b_bdev = NULL; return may_free; }