mainlining shenanigans
ecca8f88da
Now in sctp_setsockopt_maxseg user_frag or frag_point can be set with val >= 8 and val <= SCTP_MAX_CHUNK_LEN. But both checks are incorrect. val >= 8 means frag_point can even be less than SCTP_DEFAULT_MINSEGMENT. Then in sctp_datamsg_from_user(), when it's value is greater than cookie echo len and trying to bundle with cookie echo chunk, the first_len will overflow. The worse case is when it's value is equal as cookie echo len, first_len becomes 0, it will go into a dead loop for fragment later on. In Hangbin syzkaller testing env, oom was even triggered due to consecutive memory allocation in that loop. Besides, SCTP_MAX_CHUNK_LEN is the max size of the whole chunk, it should deduct the data header for frag_point or user_frag check. This patch does a proper check with SCTP_DEFAULT_MINSEGMENT subtracting the sctphdr and datahdr, SCTP_MAX_CHUNK_LEN subtracting datahdr when setting frag_point via sockopt. It also improves sctp_setsockopt_maxseg codes. Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Reported-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| 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 | ||
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.