Commit Graph

7 Commits

Author SHA1 Message Date
David Woodhouse 199bc9ff5c jffs2: Fix memory corruption in jffs2_read_inode_range()
In 2.6.23 kernel, commit a32ea1e1f9
("Fix read/truncate race") fixed a race in the generic code, and as a
side effect, now do_generic_file_read() can ask us to readpage() past
the i_size. This seems to be correctly handled by the block routines
(e.g. block_read_full_page() fills the page with zeroes in case if
somebody is trying to read past the last inode's block).

JFFS2 doesn't handle this; it assumes that it won't be asked to read
pages which don't exist -- and thus that there will be at least _one_
valid 'frag' on the page it's being asked to read. It will fill any
holes with the following memset:

  memset(buf, 0, min(end, frag->ofs + frag->size) - offset);

When the 'closest smaller match' returned by jffs2_lookup_node_frag() is
actually on a previous page and ends before 'offset', that results in:

  memset(buf, 0, <huge unsigned negative>);

Hopefully, in most cases the corruption is fatal, and quickly causing
random oopses, like this:

  root@10.0.0.4:~/ltp-fs-20090531# ./testcases/kernel/fs/ftest/ftest01
  Unable to handle kernel paging request for data at address 0x00000008
  Faulting instruction address: 0xc01cd980
  Oops: Kernel access of bad area, sig: 11 [#1]
  [...]
  NIP [c01cd980] rb_insert_color+0x38/0x184
  LR [c0043978] enqueue_hrtimer+0x88/0xc4
  Call Trace:
  [c6c63b60] [c004f9a8] tick_sched_timer+0xa0/0xe4 (unreliable)
  [c6c63b80] [c0043978] enqueue_hrtimer+0x88/0xc4
  [c6c63b90] [c0043a48] __run_hrtimer+0x94/0xbc
  [c6c63bb0] [c0044628] hrtimer_interrupt+0x140/0x2b8
  [c6c63c10] [c000f8e8] timer_interrupt+0x13c/0x254
  [c6c63c30] [c001352c] ret_from_except+0x0/0x14
  --- Exception: 901 at memset+0x38/0x5c
      LR = jffs2_read_inode_range+0x144/0x17c
  [c6c63cf0] [00000000] (null) (unreliable)

This patch fixes the issue, plus fixes all LTP tests on NAND/UBI with
JFFS2 filesystem that were failing since 2.6.23 (seems like the bug
above also broke the truncation).

Reported-By: Anton Vorontsov <avorontsov@ru.mvista.com>
Tested-By: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-30 13:52:40 -08:00
David Woodhouse c00c310eac [JFFS2] Tidy up licensing/copyright boilerplate.
In particular, remove the bit in the LICENCE file about contacting
Red Hat for alternative arrangements. Their errant IS department broke
that arrangement a long time ago -- the policy of collecting copyright
assignments from contributors came to an end when the plug was pulled on
the servers hosting the project, without notice or reason.

We do still dual-license it for use with eCos, with the GPL+exception
licence approved by the FSF as being GPL-compatible. It's just that nobody
has the right to license it differently.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2007-04-25 14:16:47 +01:00
Thomas Gleixner 182ec4eee3 [JFFS2] Clean up trailing white spaces
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-11-07 14:18:56 +01:00
Artem B. Bityutskiy e0c8e42f8f [JFFS2] Debug code clean up - step 3
Various simplifiactions. printk format corrections.
Convert more code to use the new debug functions.

Signed-off-by: Artem B. Bityutskiy <dedekind@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-11-06 17:06:49 +01:00
Artem B. Bityutskiy 730554d946 [JFFS2] Debug code clean up - step 1
Move debug functions into a seperate source file

Signed-off-by: Artem B. Bityutskiy <dedekind@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-11-06 16:21:25 +01:00
Artem B. Bityuckiy 32f1a95d50 [JFFS2] Add symlink caching support.
Signed-off-by: Artem B. Bityuckiy <dedekind@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-05-23 12:48:15 +02:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00