1a4a5bf52a
The current codes only deal with the case that the skb is dropped, it may meet one use-after-free issue when NF_HOOK returns 0 that means the skb is stolen by one netfilter rule or hook. When one netfilter rule or hook stoles the skb and return NF_STOLEN, it means the skb is taken by the rule, and other modules should not touch this skb ever. Maybe the skb is queued or freed directly by the rule. Now uses the nf_hook instead of NF_HOOK to get the result of netfilter, and check the return value of nf_hook. Only when its value equals 1, it means the skb could go ahead. Or reset the skb as NULL. BTW, because vrf_rcv_finish is empty function, so needn't invoke it even though nf_hook returns 1. But we need to modify vrf_rcv_finish to deal with the NF_STOLEN case. There are two cases when skb is stolen. 1. The skb is stolen and freed directly. There is nothing we need to do, and vrf_rcv_finish isn't invoked. 2. The skb is queued and reinjected again. The vrf_rcv_finish would be invoked as okfn, so need to free the skb in it. Signed-off-by: Gao Feng <gfree.wind@vip.163.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| Documentation | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.