[v4,3/4] Mark functions with the latent_entropy attribute

Message ID	20160620204234.01f3b0d1f825390fd694e430@gmail.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <kernel-hardening-return-3531-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com> Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk Reply-To: kernel-hardening@lists.openwall.com Date: Mon, 20 Jun 2016 20:42:34 +0200 From: Emese Revfy <re.emese@gmail.com> To: kernel-hardening@lists.openwall.com Cc: pageexec@freemail.hu, spender@grsecurity.net, mmarek@suse.com, keescook@chromium.org, linux-kernel@vger.kernel.org, yamada.masahiro@socionext.com, linux-kbuild@vger.kernel.org, tytso@mit.edu, akpm@linux-foundation.org, linux-mm@kvack.org, axboe@kernel.dk, viro@zeniv.linux.org.uk, paulmck@linux.vnet.ibm.com, mingo@redhat.com, tglx@linutronix.de, bart.vanassche@sandisk.com, davem@davemloft.net Message-Id: <20160620204234.01f3b0d1f825390fd694e430@gmail.com> In-Reply-To: <20160620203910.a8b6b5b10d18f24661916e7b@gmail.com> References: <20160620203910.a8b6b5b10d18f24661916e7b@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: [kernel-hardening] [PATCH v4 3/4] Mark functions with the latent_entropy attribute

diff --git a/block/blk-softirq.c b/block/blk-softirq.c index 53b1737..489eab8 100644 --- a/block/blk-softirq.c +++ b/block/blk-softirq.c @@ -18,7 +18,7 @@ static DEFINE_PER_CPU(struct list_head, blk_cpu_done); * Softirq action handler - move entries to local list and loop over them * while passing them to the queue registered handler. */ -static void blk_done_softirq(struct softirq_action *h) +static __latent_entropy void blk_done_softirq(struct softirq_action *h) { struct list_head *cpu_list, local_list; diff --git a/drivers/char/random.c b/drivers/char/random.c index 0158d3b..6cca3ed 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -443,9 +443,9 @@ struct entropy_store { }; static void push_to_pool(struct work_struct *work); -static __u32 input_pool_data[INPUT_POOL_WORDS]; -static __u32 blocking_pool_data[OUTPUT_POOL_WORDS]; -static __u32 nonblocking_pool_data[OUTPUT_POOL_WORDS]; +static __u32 input_pool_data[INPUT_POOL_WORDS] __latent_entropy; +static __u32 blocking_pool_data[OUTPUT_POOL_WORDS] __latent_entropy; +static __u32 nonblocking_pool_data[OUTPUT_POOL_WORDS] __latent_entropy; static struct entropy_store input_pool = { .poolinfo = &poolinfo_table[0], diff --git a/fs/namespace.c b/fs/namespace.c index 4fb1691..0951eca 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2778,6 +2778,7 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns) return new_ns; } +__latent_entropy struct mnt_namespace *copy_mnt_ns(unsigned long flags, struct mnt_namespace *ns, struct user_namespace *user_ns, struct fs_struct *new_fs) { diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index e294939..0ef8329 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -188,6 +188,13 @@ #endif /* GCC_VERSION >= 40300 */ #if GCC_VERSION >= 40500 + +#ifndef __CHECKER__ +#ifdef LATENT_ENTROPY_PLUGIN +#define __latent_entropy __attribute__((latent_entropy)) +#endif +#endif + /* * Mark a position in code as unreachable. This can be used to * suppress control flow warnings after asm blocks that transfer diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 793c082..c65327b 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -425,6 +425,10 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s # define __attribute_const__ /* unimplemented */ #endif +#ifndef __latent_entropy +# define __latent_entropy +#endif + /* * Tell gcc if a function is cold. The compiler will assume any path * directly leading to the call is unlikely. diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index 5295535..9852c7e 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -105,7 +105,7 @@ struct files_struct *get_files_struct(struct task_struct *); void put_files_struct(struct files_struct *fs); void reset_files_struct(struct files_struct *); int unshare_files(struct files_struct **); -struct files_struct *dup_fd(struct files_struct *, int *); +struct files_struct *dup_fd(struct files_struct *, int *) __latent_entropy; void do_close_on_exec(struct files_struct *); int iterate_fd(struct files_struct *, unsigned, int (*)(const void *, struct file *, unsigned), diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 359a8e4..8736c1f 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -433,7 +433,7 @@ extern void disk_flush_events(struct gendisk *disk, unsigned int mask); extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask); /* drivers/char/random.c */ -extern void add_disk_randomness(struct gendisk *disk); +extern void add_disk_randomness(struct gendisk *disk) __latent_entropy; extern void rand_initialize_disk(struct gendisk *disk); static inline sector_t get_start_sect(struct block_device *bdev) diff --git a/include/linux/init.h b/include/linux/init.h index aedb254..88646cb 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -39,7 +39,7 @@ /* These are for everybody (although not all archs will actually discard it in modules) */ -#define __init __section(.init.text) __cold notrace +#define __init __section(.init.text) __cold notrace __latent_entropy #define __initdata __section(.init.data) #define __initconst __constsection(.init.rodata) #define __exitdata __section(.exit.data) @@ -92,7 +92,8 @@ #define __exit __section(.exit.text) __exitused __cold notrace /* Used for MEMORY_HOTPLUG */ -#define __meminit __section(.meminit.text) __cold notrace +#define __meminit __section(.meminit.text) __cold notrace \ + __latent_entropy #define __meminitdata __section(.meminit.data) #define __meminitconst __constsection(.meminit.rodata) #define __memexit __section(.memexit.text) __exitused __cold notrace diff --git a/include/linux/random.h b/include/linux/random.h index 752e7df..d286d51 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -29,8 +29,8 @@ static inline void add_latent_entropy(void) {} #endif extern void add_input_randomness(unsigned int type, unsigned int code, - unsigned int value); -extern void add_interrupt_randomness(int irq, int irq_flags); + unsigned int value) __latent_entropy; +extern void add_interrupt_randomness(int irq, int irq_flags) __latent_entropy; extern void get_random_bytes(void *buf, int nbytes); extern int add_random_ready_callback(struct random_ready_callback *rdy); diff --git a/kernel/fork.c b/kernel/fork.c index fd1b3c2..8b1e313 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -406,7 +406,8 @@ free_tsk: } #ifdef CONFIG_MMU -static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) +static __latent_entropy int dup_mmap(struct mm_struct *mm, + struct mm_struct *oldmm) { struct vm_area_struct *mpnt, *tmp, *prev, **pprev; struct rb_node **rb_link, *rb_parent; @@ -1277,7 +1278,8 @@ init_task_pid(struct task_struct *task, enum pid_type type, struct pid *pid) * parts of the process environment (as per the clone * flags). The actual kick-off is left to the caller. */ -static struct task_struct *copy_process(unsigned long clone_flags, +static __latent_entropy struct task_struct *copy_process( + unsigned long clone_flags, unsigned long stack_start, unsigned long stack_size, int __user *child_tidptr, diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index 944b1b4..1898559 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -170,7 +170,7 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp) false)); } -static void rcu_process_callbacks(struct softirq_action *unused) +static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused) { __rcu_process_callbacks(&rcu_sched_ctrlblk); __rcu_process_callbacks(&rcu_bh_ctrlblk); diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index c7f1bc4..8821fce 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3004,7 +3004,7 @@ __rcu_process_callbacks(struct rcu_state *rsp) /* * Do RCU core processing for the current CPU. */ -static void rcu_process_callbacks(struct softirq_action *unused) +static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused) { struct rcu_state *rsp; diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 218f8e8..cd745c2 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -8205,7 +8205,7 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle) { } * run_rebalance_domains is triggered when needed from the scheduler tick. * Also triggered for nohz idle balancing (with nohz_balancing_kick set). */ -static void run_rebalance_domains(struct softirq_action *h) +static __latent_entropy void run_rebalance_domains(struct softirq_action *h) { struct rq *this_rq = this_rq(); enum cpu_idle_type idle = this_rq->idle_balance ? diff --git a/kernel/softirq.c b/kernel/softirq.c index 17caf4b..34033fd 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -482,7 +482,7 @@ void __tasklet_hi_schedule_first(struct tasklet_struct *t) } EXPORT_SYMBOL(__tasklet_hi_schedule_first); -static void tasklet_action(struct softirq_action *a) +static __latent_entropy void tasklet_action(struct softirq_action *a) { struct tasklet_struct *list; @@ -518,7 +518,7 @@ static void tasklet_action(struct softirq_action *a) } } -static void tasklet_hi_action(struct softirq_action *a) +static __latent_entropy void tasklet_hi_action(struct softirq_action *a) { struct tasklet_struct *list; diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 3a95f97..6008e7ae 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -1414,7 +1414,7 @@ void update_process_times(int user_tick) /* * This function runs timers and the timer-tq in bottom half context. */ -static void run_timer_softirq(struct softirq_action *h) +static __latent_entropy void run_timer_softirq(struct softirq_action *h) { struct tvec_base *base = this_cpu_ptr(&tvec_bases); diff --git a/lib/irq_poll.c b/lib/irq_poll.c index 836f7db..63be749 100644 --- a/lib/irq_poll.c +++ b/lib/irq_poll.c @@ -74,7 +74,7 @@ void irq_poll_complete(struct irq_poll *iop) } EXPORT_SYMBOL(irq_poll_complete); -static void irq_poll_softirq(struct softirq_action *h) +static void __latent_entropy irq_poll_softirq(struct softirq_action *h) { struct list_head *list = this_cpu_ptr(&blk_cpu_iopoll); int rearm = 0, budget = irq_poll_budget; diff --git a/lib/random32.c b/lib/random32.c index 510d1ce..722d2b6 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -47,7 +47,7 @@ static inline void prandom_state_selftest(void) } #endif -static DEFINE_PER_CPU(struct rnd_state, net_rand_state); +static DEFINE_PER_CPU(struct rnd_state, net_rand_state) __latent_entropy; /** * prandom_u32_state - seeded pseudo-random number generator. diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d10324e..ffc4f4a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1235,7 +1235,7 @@ static void __free_pages_ok(struct page *page, unsigned int order) } #ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY -volatile u64 latent_entropy; +volatile u64 latent_entropy __latent_entropy; EXPORT_SYMBOL(latent_entropy); #endif diff --git a/net/core/dev.c b/net/core/dev.c index 904ff43..723d3af 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3851,7 +3851,7 @@ int netif_rx_ni(struct sk_buff *skb) } EXPORT_SYMBOL(netif_rx_ni); -static void net_tx_action(struct softirq_action *h) +static __latent_entropy void net_tx_action(struct softirq_action *h) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); @@ -5175,7 +5175,7 @@ out_unlock: return work; } -static void net_rx_action(struct softirq_action *h) +static __latent_entropy void net_rx_action(struct softirq_action *h) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); unsigned long time_limit = jiffies + 2;

[v4,3/4] Mark functions with the latent_entropy attribute

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