4.20-stable review patch. If anyone has any objections, please let me know.
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From: Eric Biggers ebiggers@google.com
commit 57b0e31453209d746c99e513d80b3d0c44a80891 upstream.
We need to check the return value of match_token() for Opt_err before doing anything with it.
[ Not only did the old "-1" value for Opt_err cause problems for the __test_and_set_bit(), as fixed in commit 94c13f66e13c ("security: don't use a negative Opt_err token index"), but accessing "args[0].from" is invalid for the Opt_err case, as pointed out by Eric later. - Linus ]
Reported-by: syzbot+a22e0dc07567662c50bc@syzkaller.appspotmail.com Fixes: 00d60fd3b932 ("KEYS: Provide keyctls to drive the new key type ops for asymmetric keys [ver #2]") Signed-off-by: Eric Biggers ebiggers@google.com Cc: stable@kernel.org # 4.20 Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- security/keys/keyctl_pkey.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/security/keys/keyctl_pkey.c +++ b/security/keys/keyctl_pkey.c @@ -50,6 +50,8 @@ static int keyctl_pkey_params_parse(stru if (*p == '\0' || *p == ' ' || *p == '\t') continue; token = match_token(p, param_keys, args); + if (token == Opt_err) + return -EINVAL; if (__test_and_set_bit(token, &token_mask)) return -EINVAL; q = args[0].from;