2020-04-01 07:09:19

by chenzhou

Subject: [PATCH -next] smack: fix a missing-check bug in smack_sb_eat_lsm_opts()

In smack_sb_eat_lsm_opts(), 'arg' is allocated by kmemdup_nul().
It returns NULL when fails, add check for it.

Signed-off-by: Chen Zhou <[email protected]>
---
security/smack/smack_lsm.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 2862fc3..9ec30f3 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -731,6 +731,8 @@ static int smack_sb_eat_lsm_opts(char *options, void **mnt_opts)
token = match_opt_prefix(from, len, &arg);
if (token != Opt_error) {
arg = kmemdup_nul(arg, from + len - arg, GFP_KERNEL);
+ if (!arg)
+ return -ENOMEM;
rc = smack_add_opt(token, arg, mnt_opts);
if (unlikely(rc)) {
kfree(arg);
--
2.7.4

2020-04-01 12:40:45

by Tetsuo Handa

Subject: Re: [PATCH -next] smack: fix a missing-check bug in smack_sb_eat_lsm_opts()

On 2020/04/01 16:10, Chen Zhou wrote:
> In smack_sb_eat_lsm_opts(), 'arg' is allocated by kmemdup_nul().
> It returns NULL when fails, add check for it.

Thanks. But this check is not needed, for smack_add_opt() returns NULL if arg == NULL.