user/sven/linux.git/kernel/module.c, branch v4.8.5

Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2016-08-04T13:14:38Z

Pull module updates from Rusty Russell: "The only interesting thing here is Jessica's patch to add ro_after_init support to modules. The rest are all trivia" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: extable.h: add stddef.h so "NULL" definition is not implicit modules: add ro_after_init support jump_label: disable preemption around __module_text_address(). exceptions: fork exception table content from module.h into extable.h modules: Add kernel parameter to blacklist modules module: Do a WARN_ON_ONCE() for assert module mutex not held Documentation/module-signing.txt: Note need for version info if reusing a key module: Invalidate signatures on force-loaded modules module: Issue warnings when tainting kernel module: fix redundant test. module: fix noreturn attribute for __module_put_and_exit()

modules: add ro_after_init support

2016-08-04T00:46:55Z

Add ro_after_init support for modules by adding a new page-aligned section in the module layout (after rodata) for ro_after_init data and enabling RO protection for that section after module init runs. Signed-off-by: Jessica Yu Acked-by: Kees Cook Signed-off-by: Rusty Russell

modules: Add kernel parameter to blacklist modules

2016-08-04T00:46:53Z

Blacklisting a module in linux has long been a problem. The current procedure is to use rd.blacklist=module_name, however, that doesn't cover the case after the initramfs and before a boot prompt (where one is supposed to use /etc/modprobe.d/blacklist.conf to blacklist runtime loading). Using rd.shell to get an early prompt is hit-or-miss, and doesn't cover all situations AFAICT. This patch adds this functionality of permanently blacklisting a module by its name via the kernel parameter module_blacklist=module_name. [v2]: Rusty, use core_param() instead of __setup() which simplifies things. [v3]: Rusty, undo wreckage from strsep() [v4]: Rusty, simpler version of blacklisted() Signed-off-by: Prarit Bhargava Cc: Jonathan Corbet Cc: Rusty Russell Cc: linux-doc@vger.kernel.org Signed-off-by: Rusty Russell

module: Do a WARN_ON_ONCE() for assert module mutex not held

2016-08-04T00:46:52Z

When running with lockdep enabled, I triggered the WARN_ON() in the module code that asserts when module_mutex or rcu_read_lock_sched are not held. The issue I have is that this can also be called from the dump_stack() code, causing us to enter an infinite loop... ------------[ cut here ]------------ WARNING: CPU: 1 PID: 0 at kernel/module.c:268 module_assert_mutex_or_preempt+0x3c/0x3e Modules linked in: ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.7.0-rc3-test-00013-g501c2375253c #14 Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014 ffff880215e8fa70 ffff880215e8fa70 ffffffff812fc8e3 0000000000000000 ffffffff81d3e55b ffff880215e8fac0 ffffffff8104fc88 ffffffff8104fcab 0000000915e88300 0000000000000046 ffffffffa019b29a 0000000000000001 Call Trace: [] dump_stack+0x67/0x90 [] __warn+0xcb/0xe9 [] ? warn_slowpath_null+0x5/0x1f ------------[ cut here ]------------ WARNING: CPU: 1 PID: 0 at kernel/module.c:268 module_assert_mutex_or_preempt+0x3c/0x3e Modules linked in: ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.7.0-rc3-test-00013-g501c2375253c #14 Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014 ffff880215e8f7a0 ffff880215e8f7a0 ffffffff812fc8e3 0000000000000000 ffffffff81d3e55b ffff880215e8f7f0 ffffffff8104fc88 ffffffff8104fcab 0000000915e88300 0000000000000046 ffffffffa019b29a 0000000000000001 Call Trace: [] dump_stack+0x67/0x90 [] __warn+0xcb/0xe9 [] ? warn_slowpath_null+0x5/0x1f ------------[ cut here ]------------ WARNING: CPU: 1 PID: 0 at kernel/module.c:268 module_assert_mutex_or_preempt+0x3c/0x3e Modules linked in: ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.7.0-rc3-test-00013-g501c2375253c #14 Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014 ffff880215e8f4d0 ffff880215e8f4d0 ffffffff812fc8e3 0000000000000000 ffffffff81d3e55b ffff880215e8f520 ffffffff8104fc88 ffffffff8104fcab 0000000915e88300 0000000000000046 ffffffffa019b29a 0000000000000001 Call Trace: [] dump_stack+0x67/0x90 [] __warn+0xcb/0xe9 [] ? warn_slowpath_null+0x5/0x1f ------------[ cut here ]------------ WARNING: CPU: 1 PID: 0 at kernel/module.c:268 module_assert_mutex_or_preempt+0x3c/0x3e [...] Which gives us rather useless information. Worse yet, there's some race that causes this, and I seldom trigger it, so I have no idea what happened. This would not be an issue if that warning was a WARN_ON_ONCE(). Signed-off-by: Steven Rostedt Signed-off-by: Rusty Russell

dynamic_debug: only add header when used

2016-08-02T23:35:03Z

kernel.h header doesn't directly use dynamic debug, instead we can include it in module.c (which used it via kernel.h). printk.h only uses it if CONFIG_DYNAMIC_DEBUG is on, changing the inclusion to only happen in that case. Link: http://lkml.kernel.org/r/1468429793-16917-1-git-send-email-luisbg@osg.samsung.com [luisbg@osg.samsung.com: include dynamic_debug.h in drb_int.h] Link: http://lkml.kernel.org/r/1468447828-18558-2-git-send-email-luisbg@osg.samsung.com Signed-off-by: Luis de Bethencourt Cc: Rusty Russell Cc: Hidehiro Kawai Cc: Borislav Petkov Cc: Michal Nazarewicz Cc: Rasmus Villemoes Cc: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

module: Invalidate signatures on force-loaded modules

2016-07-27T03:08:00Z

Signing a module should only make it trusted by the specific kernel it was built for, not anything else. Loading a signed module meant for a kernel with a different ABI could have interesting effects. Therefore, treat all signatures as invalid when a module is force-loaded. Signed-off-by: Ben Hutchings Cc: stable@vger.kernel.org Signed-off-by: Rusty Russell

module: Issue warnings when tainting kernel

2016-07-27T03:08:00Z

While most of the locations where a kernel taint bit is set are accompanied with a warning message, there are two which set their bits silently. If the tainting module gets unloaded later on, it is almost impossible to tell what was the reason for setting the flag. Signed-off-by: Libor Pechacek Signed-off-by: Rusty Russell

module: fix redundant test.

2016-07-27T03:08:00Z

[linux-4.5-rc4/kernel/module.c:1692]: (style) Redundant condition: attr.test. '!attr.test || (attr.test && attr.test(mod))' is equivalent to '!attr.test || attr.test(mod)' This code was added like this ten years ago, in c988d2b284549 "modules: add version and srcversion to sysfs". Reported-by: David Binderman Cc: Matt Domsch Signed-off-by: Rusty Russell

module: fix noreturn attribute for __module_put_and_exit()

2016-07-27T03:08:00Z

__module_put_and_exit() is makred noreturn in module.h declaration, but is lacking the attribute in the definition, which makes some tools (such as sparse) unhappy. Amend the definition with the attribute as well (and reformat the declaration so that it uses more common format). Signed-off-by: Jiri Kosina Signed-off-by: Rusty Russell

module: preserve Elf information for livepatch modules

2016-04-01T13:00:10Z

For livepatch modules, copy Elf section, symbol, and string information from the load_info struct in the module loader. Persist copies of the original symbol table and string table. Livepatch manages its own relocation sections in order to reuse module loader code to write relocations. Livepatch modules must preserve Elf information such as section indices in order to apply livepatch relocation sections using the module loader's apply_relocate_add() function. In order to apply livepatch relocation sections, livepatch modules must keep a complete copy of their original symbol table in memory. Normally, a stripped down copy of a module's symbol table (containing only "core" symbols) is made available through module->core_symtab. But for livepatch modules, the symbol table copied into memory on module load must be exactly the same as the symbol table produced when the patch module was compiled. This is because the relocations in each livepatch relocation section refer to their respective symbols with their symbol indices, and the original symbol indices (and thus the symtab ordering) must be preserved in order for apply_relocate_add() to find the right symbol. Signed-off-by: Jessica Yu Reviewed-by: Miroslav Benes Acked-by: Josh Poimboeuf Acked-by: Rusty Russell Reviewed-by: Rusty Russell Signed-off-by: Jiri Kosina