forked from luck/tmp_suning_uos_patched
a84b8b53a5
commit e27326009a3d247b831eda38878c777f6f4eb3d1 upstream.
When we close ping6 sockets, some resources are left unfreed because
pingv6_prot is missing sk->sk_prot->destroy(). As reported by
syzbot [0], just three syscalls leak 96 bytes and easily cause OOM.
struct ipv6_sr_hdr *hdr;
char data[24] = {0};
int fd;
hdr = (struct ipv6_sr_hdr *)data;
hdr->hdrlen = 2;
hdr->type = IPV6_SRCRT_TYPE_4;
fd = socket(AF_INET6, SOCK_DGRAM, NEXTHDR_ICMP);
setsockopt(fd, IPPROTO_IPV6, IPV6_RTHDR, data, 24);
close(fd);
To fix memory leaks, let's add a destroy function.
Note the socket() syscall checks if the GID is within the range of
net.ipv4.ping_group_range. The default value is [1, 0] so that no
GID meets the condition (1 <= GID <= 0). Thus, the local DoS does
not succeed until we change the default value. However, at least
Ubuntu/Fedora/RHEL loosen it.
$ cat /usr/lib/sysctl.d/50-default.conf
...
-net.ipv4.ping_group_range = 0 2147483647
Also, there could be another path reported with these options, and
some of them require CAP_NET_RAW.
setsockopt
IPV6_ADDRFORM (inet6_sk(sk)->pktoptions)
IPV6_RECVPATHMTU (inet6_sk(sk)->rxpmtu)
IPV6_HOPOPTS (inet6_sk(sk)->opt)
IPV6_RTHDRDSTOPTS (inet6_sk(sk)->opt)
IPV6_RTHDR (inet6_sk(sk)->opt)
IPV6_DSTOPTS (inet6_sk(sk)->opt)
IPV6_2292PKTOPTIONS (inet6_sk(sk)->opt)
getsockopt
IPV6_FLOWLABEL_MGR (inet6_sk(sk)->ipv6_fl_list)
For the record, I left a different splat with syzbot's one.
unreferenced object 0xffff888006270c60 (size 96):
comm "repro2", pid 231, jiffies 4294696626 (age 13.118s)
hex dump (first 32 bytes):
01 00 00 00 44 00 00 00 00 00 00 00 00 00 00 00 ....D...........
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000f6bc7ea9>] sock_kmalloc (net/core/sock.c:2564 net/core/sock.c:2554)
[<000000006d699550>] do_ipv6_setsockopt.constprop.0 (net/ipv6/ipv6_sockglue.c:715)
[<00000000c3c3b1f5>] ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:1024)
[<000000007096a025>] __sys_setsockopt (net/socket.c:2254)
[<000000003a8ff47b>] __x64_sys_setsockopt (net/socket.c:2265 net/socket.c:2262 net/socket.c:2262)
[<000000007c409dcb>] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
[<00000000e939c4a9>] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
[0]: https://syzkaller.appspot.com/bug?extid=a8430774139ec3ab7176
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| 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.
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.