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Andrey Ryabinin 2045cdfa1b netfilter: nf_conntrack: Fix possible possible crash on module loading.
Loading the nf_conntrack module with doubled hashsize parameter, i.e.
	  modprobe nf_conntrack hashsize=12345 hashsize=12345
causes NULL-ptr deref.

If 'hashsize' specified twice, the nf_conntrack_set_hashsize() function
will be called also twice.
The first nf_conntrack_set_hashsize() call will set the
'nf_conntrack_htable_size' variable:

	nf_conntrack_set_hashsize()
		...
		/* On boot, we can set this without any fancy locking. */
		if (!nf_conntrack_htable_size)
			return param_set_uint(val, kp);

But on the second invocation, the nf_conntrack_htable_size is already set,
so the nf_conntrack_set_hashsize() will take a different path and call
the nf_conntrack_hash_resize() function. Which will crash on the attempt
to dereference 'nf_conntrack_hash' pointer:

	BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
	RIP: 0010:nf_conntrack_hash_resize+0x255/0x490 [nf_conntrack]
	Call Trace:
	 nf_conntrack_set_hashsize+0xcd/0x100 [nf_conntrack]
	 parse_args+0x1f9/0x5a0
	 load_module+0x1281/0x1a50
	 __se_sys_finit_module+0xbe/0xf0
	 do_syscall_64+0x7c/0x390
	 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fix this, by checking !nf_conntrack_hash instead of
!nf_conntrack_htable_size. nf_conntrack_hash will be initialized only
after the module loaded, so the second invocation of the
nf_conntrack_set_hashsize() won't crash, it will just reinitialize
nf_conntrack_htable_size again.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-07-09 18:04:11 +02:00
arch OpenRISC fixes for 4.18 2018-07-02 12:38:14 -07:00
block for-linus-20180629 2018-06-30 10:47:46 -07:00
certs certs/blacklist: fix const confusion 2018-06-26 09:43:03 -07:00
crypto Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
Documentation USB fixes for 4.18-rc3 2018-07-01 11:50:16 -07:00
drivers smsc75xx: Add workaround for gigabit link up hardware errata. 2018-07-04 22:12:59 +09:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs for-4.18-rc2-tag 2018-07-01 12:38:16 -07:00
include netfilter: nf_tables: place all set backends in one single module 2018-07-06 19:31:53 +02:00
init Kbuild fixes for v4.18 2018-06-30 13:05:30 -07:00
ipc ipc: use new return type vm_fault_t 2018-06-15 07:55:25 +09:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
lib lib: rhashtable: Correct self-assignment in rhashtable.c 2018-07-03 23:25:37 +09:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm slub: fix failure when we delete and create a slab cache 2018-06-28 11:16:44 -07:00
net netfilter: nf_conntrack: Fix possible possible crash on module loading. 2018-07-09 18:04:11 +02:00
samples bpf: Change bpf_fib_lookup to return lookup status 2018-06-29 00:02:02 +02:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
security selinux/stable-4.18 PR 20180629 2018-06-30 11:15:12 -07:00
sound ALSA: seq: Fix UBSAN warning at SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT ioctl 2018-06-25 11:18:04 +02:00
tools net/ipv6: Revert attempt to simplify route replace and append 2018-07-04 15:22:13 +09:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt KVM: arm64: Prevent KVM_COMPAT from being selected 2018-06-21 17:17:50 +01:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap Merge branch 'asoc-4.17' into asoc-4.18 for compress dependencies 2018-04-26 12:24:28 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: add basic helper macros to scripts/Kconfig.include 2018-05-29 03:31:19 +09:00
MAINTAINERS wireless-drivers fixes for 4.18 2018-07-03 23:29:29 +09:00
Makefile Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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.