[PATCH] fs, omfs: add NULL terminator in the end up the token list

[PATCH] fs, omfs: add NULL terminator in the end up the token list

[Sasha Levin]

match_token() expects a NULL terminator at the end of the token list so that
it would know where to stop. Not having one causes it to overrun to invalid
memory.

In practice, passing a mount option that omfs didn't recognize would sometimes
panic the system.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
---
 fs/omfs/inode.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/omfs/inode.c b/fs/omfs/inode.c
index 138321b..70d4191 100644
--- a/fs/omfs/inode.c
+++ b/fs/omfs/inode.c
@@ -359,7 +359,7 @@ nomem:
 }
 
 enum {
-	Opt_uid, Opt_gid, Opt_umask, Opt_dmask, Opt_fmask
+	Opt_uid, Opt_gid, Opt_umask, Opt_dmask, Opt_fmask, Opt_err
 };
 
 static const match_table_t tokens = {
@@ -368,6 +368,7 @@ static const match_table_t tokens = {
 	{Opt_umask, "umask=%o"},
 	{Opt_dmask, "dmask=%o"},
 	{Opt_fmask, "fmask=%o"},
+	{Opt_err, NULL},
 };
 
 static int parse_options(char *options, struct omfs_sb_info *sbi)
-- 
1.7.10.4

Re: [PATCH] fs, omfs: add NULL terminator in the end up the token list

[Bob Copeland]

On Thu, Mar 12, 2015 at 04:11:09PM -0400, Sasha Levin wrote:
> match_token() expects a NULL terminator at the end of the token list so that
> it would know where to stop. Not having one causes it to overrun to invalid
> memory.
> 
> In practice, passing a mount option that omfs didn't recognize would sometimes
> panic the system.

Yikes, thanks for the catch!

Acked-by: Bob Copeland <me@bobcopeland.com>

> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

-- 
Bob Copeland %% http://bobcopeland.com/