diff options
| author | Benjamin LaHaise <bcrl@kvack.org> | 2014-06-24 13:32:51 -0400 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2014-08-19 16:25:32 +1000 |
| commit | f04c5dee8422b1d3d725644e1adc48d2151f6aeb (patch) | |
| tree | 9d3fafd62a272838fb2d140db27b03b4960df97e | |
| parent | 921b1130a9c76a9c88f8568b33faab083072879e (diff) | |
| download | powerpc-powerkvm-v2.1-srvc.tar.gz | |
aio: fix kernel memory disclosure in io_getevents() introduced in v3.10powerkvm-v2.1.0.2powerkvm-v2.1-srvc
commit edfbbf388f293d70bf4b7c0bc38774d05e6f711a upstream.
A kernel memory disclosure was introduced in aio_read_events_ring() in v3.10
by commit a31ad380bed817aa25f8830ad23e1a0480fef797. The changes made to
aio_read_events_ring() failed to correctly limit the index into
ctx->ring_pages[], allowing an attacked to cause the subsequent kmap() of
an arbitrary page with a copy_to_user() to copy the contents into userspace.
This vulnerability has been assigned CVE-2014-0206. Thanks to Mateusz and
Petr for disclosing this issue.
This patch applies to v3.12+. A separate backport is needed for 3.10/3.11.
[jmoyer@redhat.com: backported to 3.10]
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Petr Matousek <pmatouse@redhat.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit d36db46c2cba973557eb6138d22210c4e0cf17d6)
Signed-off-by: Paul Mackerras <paulus@samba.org>
| -rw-r--r-- | fs/aio.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/aio.c b/fs/aio.c index 8d2c997a550c82..ded94c4fa30d31 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -717,6 +717,8 @@ static long aio_read_events_ring(struct kioctx *ctx, if (head == ctx->tail) goto out; + head %= ctx->nr_events; + while (ret < nr) { long avail; struct io_event *ev; |