dann frazier
2010-Nov-18 22:03 UTC
[Ocfs2-devel] [PATCH] [OCFS2] ocfs2_connection_find() returns pointer to bad structure
If ocfs2_live_connection_list is empty, ocfs2_connection_find() will return a pointer to the LIST_HEAD, cast as a ocfs2_live_connection. This can cause an oops when ocfs2_control_send_down() dereferences c->oc_conn: Call Trace: [<ffffffffa00c2a3c>] ocfs2_control_message+0x28c/0x2b0 [ocfs2_stack_user] [<ffffffffa00c2a95>] ocfs2_control_write+0x35/0xb0 [ocfs2_stack_user] [<ffffffff81143a88>] vfs_write+0xb8/0x1a0 [<ffffffff8155cc13>] ? do_page_fault+0x153/0x3b0 [<ffffffff811442f1>] sys_write+0x51/0x80 [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b Fix by explicitly returning NULL if no match is found. Signed-off-by: dann frazier <dann.frazier at canonical.com> --- fs/ocfs2/stack_user.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c index 252e7c8..a5ebe42 100644 --- a/fs/ocfs2/stack_user.c +++ b/fs/ocfs2/stack_user.c @@ -190,7 +190,7 @@ static struct ocfs2_live_connection *ocfs2_connection_find(const char *name) return c; } - return c; + return NULL; } /* -- 1.7.2.3
Joel Becker
2010-Nov-18 23:45 UTC
[Ocfs2-devel] [PATCH] [OCFS2] ocfs2_connection_find() returns pointer to bad structure
On Thu, Nov 18, 2010 at 03:03:09PM -0700, dann frazier wrote:> If ocfs2_live_connection_list is empty, ocfs2_connection_find() will return > a pointer to the LIST_HEAD, cast as a ocfs2_live_connection. This can cause > an oops when ocfs2_control_send_down() dereferences c->oc_conn: > > Call Trace: > [<ffffffffa00c2a3c>] ocfs2_control_message+0x28c/0x2b0 [ocfs2_stack_user] > [<ffffffffa00c2a95>] ocfs2_control_write+0x35/0xb0 [ocfs2_stack_user] > [<ffffffff81143a88>] vfs_write+0xb8/0x1a0 > [<ffffffff8155cc13>] ? do_page_fault+0x153/0x3b0 > [<ffffffff811442f1>] sys_write+0x51/0x80 > [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b > > Fix by explicitly returning NULL if no match is found. > > Signed-off-by: dann frazier <dann.frazier at canonical.com>This patch is now in the fixes branch of ocfs2.git. Joel -- "I don't even butter my bread; I consider that cooking." - Katherine Cebrian Joel Becker Senior Development Manager Oracle E-mail: joel.becker at oracle.com Phone: (650) 506-8127