Message ID | 1293062307.9820.331.camel@dan |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
From: Dan Rosenberg <drosenberg@vsecurity.com> Date: Wed, 22 Dec 2010 18:58:27 -0500 > If the user-provided len is less than the expected offset, the > IRLMP_ENUMDEVICES getsockopt will do a copy_to_user() with a very large > size value. While this isn't be a security issue on x86 because it will > get caught by the access_ok() check, it may leak large amounts of kernel > heap on other architectures. In any event, this patch fixes it. > > Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Applied, thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/irda/af_irda.c b/net/irda/af_irda.c index a6de305..241d7a0 100644 --- a/net/irda/af_irda.c +++ b/net/irda/af_irda.c @@ -2280,6 +2280,16 @@ static int irda_getsockopt(struct socket *sock, int level, int optname, switch (optname) { case IRLMP_ENUMDEVICES: + + /* Offset to first device entry */ + offset = sizeof(struct irda_device_list) - + sizeof(struct irda_device_info); + + if (len < offset) { + err = -EINVAL; + goto out; + } + /* Ask lmp for the current discovery log */ discoveries = irlmp_get_discoveries(&list.len, self->mask.word, self->nslots); @@ -2290,15 +2300,9 @@ static int irda_getsockopt(struct socket *sock, int level, int optname, } /* Write total list length back to client */ - if (copy_to_user(optval, &list, - sizeof(struct irda_device_list) - - sizeof(struct irda_device_info))) + if (copy_to_user(optval, &list, offset)) err = -EFAULT; - /* Offset to first device entry */ - offset = sizeof(struct irda_device_list) - - sizeof(struct irda_device_info); - /* Copy the list itself - watch for overflow */ if (list.len > 2048) { err = -EINVAL;
If the user-provided len is less than the expected offset, the IRLMP_ENUMDEVICES getsockopt will do a copy_to_user() with a very large size value. While this isn't be a security issue on x86 because it will get caught by the access_ok() check, it may leak large amounts of kernel heap on other architectures. In any event, this patch fixes it. Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: stable <stable@kernel.org> --- net/irda/af_irda.c | 18 +++++++++++------- 1 files changed, 11 insertions(+), 7 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html