Minimal supplement to upstream Kernel Self Protection Project changes. Features already provided by SELinux + Yama and archs other than multiarch arm64 / x86_64 aren't in scope. Only tags have stable history. Shared IRC channel with KSPP: irc.libera.chat #linux-hardening
d26ed6b0e5
This patch fixes skb_shared area, which will be corrupted
upon reception of 4K jumbo packets.
Originally build_skb usage purpose was to reuse page for skb to eliminate
needs of extra fragments. But that logic does not take into account that
skb_shared_info should be reserved at the end of skb data area.
In case packet data consumes all the page (4K), skb_shinfo location
overflows the page. As a consequence, __build_skb zeroed shinfo data above
the allocated page, corrupting next page.
The issue is rarely seen in real life because jumbo are normally larger
than 4K and that causes another code path to trigger.
But it 100% reproducible with simple scapy packet, like:
sendp(IP(dst="192.168.100.3") / TCP(dport=443) \
/ Raw(RandString(size=(4096-40))), iface="enp1s0")
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
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.