* [PATCH 0/2] binder: tell userspace to dump current backtrace when detected oneway spamming
@ 2021-04-09 9:40 Hang Lu
2021-04-09 9:40 ` [PATCH 1/2] binder: fix the missing BR_FROZEN_REPLY in binder_return_strings Hang Lu
2021-04-09 9:40 ` [PATCH 2/2] binder: tell userspace to dump current backtrace when detected oneway spamming Hang Lu
0 siblings, 2 replies; 5+ messages in thread
From: Hang Lu @ 2021-04-09 9:40 UTC (permalink / raw)
To: tkjos, gregkh
Cc: tkjos, maco, arve, joel, christian, hridya, surenb, rdunlap,
linux-kernel, Hang Lu
Add feature for binder oneway spamming detection, which tells userspace
to dump current backtrace. Fix the missing "BR_FROZEN_REPLY" issue first,
then features.
Hang Lu (2):
binder: fix the missing BR_FROZEN_REPLY in binder_return_strings
binder: tell userspace to dump current backtrace when detected oneway
spamming
drivers/android/binder.c | 30 ++++++++++++++++++++++++++----
drivers/android/binder_alloc.c | 15 ++++++++++++---
drivers/android/binder_alloc.h | 8 +++++++-
drivers/android/binder_internal.h | 6 +++++-
include/uapi/linux/android/binder.h | 8 ++++++++
5 files changed, 58 insertions(+), 9 deletions(-)
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH 1/2] binder: fix the missing BR_FROZEN_REPLY in binder_return_strings
2021-04-09 9:40 [PATCH 0/2] binder: tell userspace to dump current backtrace when detected oneway spamming Hang Lu
@ 2021-04-09 9:40 ` Hang Lu
2021-04-09 15:12 ` Todd Kjos
2021-04-09 9:40 ` [PATCH 2/2] binder: tell userspace to dump current backtrace when detected oneway spamming Hang Lu
1 sibling, 1 reply; 5+ messages in thread
From: Hang Lu @ 2021-04-09 9:40 UTC (permalink / raw)
To: tkjos, gregkh
Cc: tkjos, maco, arve, joel, christian, hridya, surenb, rdunlap,
linux-kernel, Hang Lu
Add BR_FROZEN_REPLY in binder_return_strings to support stat function.
Fixes: ae28c1be1e54 ("binder: BINDER_GET_FROZEN_INFO ioctl")
Signed-off-by: Hang Lu <hangl@codeaurora.org>
---
drivers/android/binder.c | 3 ++-
drivers/android/binder_internal.h | 2 +-
2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index e1a484a..be34da3 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5559,7 +5559,8 @@ static const char * const binder_return_strings[] = {
"BR_FINISHED",
"BR_DEAD_BINDER",
"BR_CLEAR_DEATH_NOTIFICATION_DONE",
- "BR_FAILED_REPLY"
+ "BR_FAILED_REPLY",
+ "BR_FROZEN_REPLY",
};
static const char * const binder_command_strings[] = {
diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h
index 2872a7d..a507166 100644
--- a/drivers/android/binder_internal.h
+++ b/drivers/android/binder_internal.h
@@ -155,7 +155,7 @@ enum binder_stat_types {
};
struct binder_stats {
- atomic_t br[_IOC_NR(BR_FAILED_REPLY) + 1];
+ atomic_t br[_IOC_NR(BR_FROZEN_REPLY) + 1];
atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1];
atomic_t obj_created[BINDER_STAT_COUNT];
atomic_t obj_deleted[BINDER_STAT_COUNT];
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 2/2] binder: tell userspace to dump current backtrace when detected oneway spamming
2021-04-09 9:40 [PATCH 0/2] binder: tell userspace to dump current backtrace when detected oneway spamming Hang Lu
2021-04-09 9:40 ` [PATCH 1/2] binder: fix the missing BR_FROZEN_REPLY in binder_return_strings Hang Lu
@ 2021-04-09 9:40 ` Hang Lu
2021-04-09 15:16 ` Todd Kjos
1 sibling, 1 reply; 5+ messages in thread
From: Hang Lu @ 2021-04-09 9:40 UTC (permalink / raw)
To: tkjos, gregkh
Cc: tkjos, maco, arve, joel, christian, hridya, surenb, rdunlap,
linux-kernel, Hang Lu
When async binder buffer got exhausted, some normal oneway transactions
will also be discarded and may cause system or application failures. By
that time, the binder debug information we dump may not be relevant to
the root cause. And this issue is difficult to debug if without the
backtrace of the thread sending spam.
This change will send BR_ONEWAY_SPAM_SUSPECT to userspace when oneway
spamming is detected, request to dump current backtrace. Oneway spamming
will be reported only once when exceeding the threshold (target process
dips below 80% of its oneway space, and current process is responsible for
either more than 50 transactions, or more than 50% of the oneway space).
And the detection will restart when the async buffer has returned to a
healthy state.
Signed-off-by: Hang Lu <hangl@codeaurora.org>
---
drivers/android/binder.c | 27 ++++++++++++++++++++++++---
drivers/android/binder_alloc.c | 15 ++++++++++++---
drivers/android/binder_alloc.h | 8 +++++++-
drivers/android/binder_internal.h | 6 +++++-
include/uapi/linux/android/binder.h | 8 ++++++++
5 files changed, 56 insertions(+), 8 deletions(-)
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index be34da3..63d2c43 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -3020,7 +3020,10 @@ static void binder_transaction(struct binder_proc *proc,
goto err_bad_object_type;
}
}
- tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
+ if (t->buffer->oneway_spam_suspect)
+ tcomplete->type = BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT;
+ else
+ tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
t->work.type = BINDER_WORK_TRANSACTION;
if (reply) {
@@ -3893,9 +3896,14 @@ static int binder_thread_read(struct binder_proc *proc,
binder_stat_br(proc, thread, cmd);
} break;
- case BINDER_WORK_TRANSACTION_COMPLETE: {
+ case BINDER_WORK_TRANSACTION_COMPLETE:
+ case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT: {
+ if (proc->oneway_spam_detection_enabled &&
+ w->type == BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT)
+ cmd = BR_ONEWAY_SPAM_SUSPECT;
+ else
+ cmd = BR_TRANSACTION_COMPLETE;
binder_inner_proc_unlock(proc);
- cmd = BR_TRANSACTION_COMPLETE;
kfree(w);
binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
if (put_user(cmd, (uint32_t __user *)ptr))
@@ -4897,6 +4905,18 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
}
break;
}
+ case BINDER_ENABLE_ONEWAY_SPAM_DETECTION: {
+ uint32_t enable;
+
+ if (copy_from_user(&enable, ubuf, sizeof(enable))) {
+ ret = -EINVAL;
+ goto err;
+ }
+ binder_inner_proc_lock(proc);
+ proc->oneway_spam_detection_enabled = (bool)enable;
+ binder_inner_proc_unlock(proc);
+ break;
+ }
default:
ret = -EINVAL;
goto err;
@@ -5561,6 +5581,7 @@ static const char * const binder_return_strings[] = {
"BR_CLEAR_DEATH_NOTIFICATION_DONE",
"BR_FAILED_REPLY",
"BR_FROZEN_REPLY",
+ "BR_ONEWAY_SPAM_SUSPECT",
};
static const char * const binder_command_strings[] = {
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index 7caf74a..340515f 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -338,7 +338,7 @@ static inline struct vm_area_struct *binder_alloc_get_vma(
return vma;
}
-static void debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
+static bool debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
{
/*
* Find the amount and size of buffers allocated by the current caller;
@@ -366,13 +366,19 @@ static void debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
/*
* Warn if this pid has more than 50 transactions, or more than 50% of
- * async space (which is 25% of total buffer size).
+ * async space (which is 25% of total buffer size). Oneway spam is only
+ * detected when the threshold is exceeded.
*/
if (num_buffers > 50 || total_alloc_size > alloc->buffer_size / 4) {
binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
"%d: pid %d spamming oneway? %zd buffers allocated for a total size of %zd\n",
alloc->pid, pid, num_buffers, total_alloc_size);
+ if (!alloc->oneway_spam_detected) {
+ alloc->oneway_spam_detected = true;
+ return true;
+ }
}
+ return false;
}
static struct binder_buffer *binder_alloc_new_buf_locked(
@@ -525,6 +531,7 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
buffer->async_transaction = is_async;
buffer->extra_buffers_size = extra_buffers_size;
buffer->pid = pid;
+ buffer->oneway_spam_suspect = false;
if (is_async) {
alloc->free_async_space -= size + sizeof(struct binder_buffer);
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
@@ -536,7 +543,9 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
* of async space left (which is less than 10% of total
* buffer size).
*/
- debug_low_async_space_locked(alloc, pid);
+ buffer->oneway_spam_suspect = debug_low_async_space_locked(alloc, pid);
+ } else {
+ alloc->oneway_spam_detected = false;
}
}
return buffer;
diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h
index 6e8e001..7dea57a 100644
--- a/drivers/android/binder_alloc.h
+++ b/drivers/android/binder_alloc.h
@@ -26,6 +26,8 @@ struct binder_transaction;
* @clear_on_free: %true if buffer must be zeroed after use
* @allow_user_free: %true if user is allowed to free buffer
* @async_transaction: %true if buffer is in use for an async txn
+ * @oneway_spam_suspect: %true if total async allocate size just exceed
+ * spamming detect threshold
* @debug_id: unique ID for debugging
* @transaction: pointer to associated struct binder_transaction
* @target_node: struct binder_node associated with this buffer
@@ -45,7 +47,8 @@ struct binder_buffer {
unsigned clear_on_free:1;
unsigned allow_user_free:1;
unsigned async_transaction:1;
- unsigned debug_id:28;
+ unsigned oneway_spam_suspect:1;
+ unsigned debug_id:27;
struct binder_transaction *transaction;
@@ -87,6 +90,8 @@ struct binder_lru_page {
* @buffer_size: size of address space specified via mmap
* @pid: pid for associated binder_proc (invariant after init)
* @pages_high: high watermark of offset in @pages
+ * @oneway_spam_detected: %true if oneway spam detection fired, clear that
+ * flag once the async buffer has returned to a healthy state
*
* Bookkeeping structure for per-proc address space management for binder
* buffers. It is normally initialized during binder_init() and binder_mmap()
@@ -107,6 +112,7 @@ struct binder_alloc {
uint32_t buffer_free;
int pid;
size_t pages_high;
+ bool oneway_spam_detected;
};
#ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST
diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h
index a507166..810c0b8 100644
--- a/drivers/android/binder_internal.h
+++ b/drivers/android/binder_internal.h
@@ -155,7 +155,7 @@ enum binder_stat_types {
};
struct binder_stats {
- atomic_t br[_IOC_NR(BR_FROZEN_REPLY) + 1];
+ atomic_t br[_IOC_NR(BR_ONEWAY_SPAM_SUSPECT) + 1];
atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1];
atomic_t obj_created[BINDER_STAT_COUNT];
atomic_t obj_deleted[BINDER_STAT_COUNT];
@@ -174,6 +174,7 @@ struct binder_work {
enum binder_work_type {
BINDER_WORK_TRANSACTION = 1,
BINDER_WORK_TRANSACTION_COMPLETE,
+ BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT,
BINDER_WORK_RETURN_ERROR,
BINDER_WORK_NODE,
BINDER_WORK_DEAD_BINDER,
@@ -409,6 +410,8 @@ struct binder_ref {
* @outer_lock: no nesting under innor or node lock
* Lock order: 1) outer, 2) node, 3) inner
* @binderfs_entry: process-specific binderfs log file
+ * @oneway_spam_detection_enabled: process enabled oneway spam detection
+ * or not
*
* Bookkeeping structure for binder processes
*/
@@ -444,6 +447,7 @@ struct binder_proc {
spinlock_t inner_lock;
spinlock_t outer_lock;
struct dentry *binderfs_entry;
+ bool oneway_spam_detection_enabled;
};
/**
diff --git a/include/uapi/linux/android/binder.h b/include/uapi/linux/android/binder.h
index 156070d..20e435f 100644
--- a/include/uapi/linux/android/binder.h
+++ b/include/uapi/linux/android/binder.h
@@ -241,6 +241,7 @@ struct binder_frozen_status_info {
#define BINDER_SET_CONTEXT_MGR_EXT _IOW('b', 13, struct flat_binder_object)
#define BINDER_FREEZE _IOW('b', 14, struct binder_freeze_info)
#define BINDER_GET_FROZEN_INFO _IOWR('b', 15, struct binder_frozen_status_info)
+#define BINDER_ENABLE_ONEWAY_SPAM_DETECTION _IOW('b', 16, __u32)
/*
* NOTE: Two special error codes you should check for when calling
@@ -428,6 +429,13 @@ enum binder_driver_return_protocol {
* The target of the last transaction (either a bcTRANSACTION or
* a bcATTEMPT_ACQUIRE) is frozen. No parameters.
*/
+
+ BR_ONEWAY_SPAM_SUSPECT = _IO('r', 19),
+ /*
+ * Current process sent too many oneway calls to target, and the last
+ * asynchronous transaction makes the allocated async buffer size exceed
+ * detection threshold. No parameters.
+ */
};
enum binder_driver_command_protocol {
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH 1/2] binder: fix the missing BR_FROZEN_REPLY in binder_return_strings
2021-04-09 9:40 ` [PATCH 1/2] binder: fix the missing BR_FROZEN_REPLY in binder_return_strings Hang Lu
@ 2021-04-09 15:12 ` Todd Kjos
0 siblings, 0 replies; 5+ messages in thread
From: Todd Kjos @ 2021-04-09 15:12 UTC (permalink / raw)
To: Hang Lu
Cc: Greg Kroah-Hartman, Todd Kjos, Martijn Coenen,
Arve Hjønnevåg, Joel Fernandes (Google),
Christian Brauner, Hridya Valsaraju, Suren Baghdasaryan, rdunlap,
LKML
+Li Li
On Fri, Apr 9, 2021 at 2:42 AM Hang Lu <hangl@codeaurora.org> wrote:
>
> Add BR_FROZEN_REPLY in binder_return_strings to support stat function.
>
> Fixes: ae28c1be1e54 ("binder: BINDER_GET_FROZEN_INFO ioctl")
> Signed-off-by: Hang Lu <hangl@codeaurora.org>
Acked-by: Todd Kjos <tkjos@google.com>
> ---
> drivers/android/binder.c | 3 ++-
> drivers/android/binder_internal.h | 2 +-
> 2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index e1a484a..be34da3 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -5559,7 +5559,8 @@ static const char * const binder_return_strings[] = {
> "BR_FINISHED",
> "BR_DEAD_BINDER",
> "BR_CLEAR_DEATH_NOTIFICATION_DONE",
> - "BR_FAILED_REPLY"
> + "BR_FAILED_REPLY",
> + "BR_FROZEN_REPLY",
> };
>
> static const char * const binder_command_strings[] = {
> diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h
> index 2872a7d..a507166 100644
> --- a/drivers/android/binder_internal.h
> +++ b/drivers/android/binder_internal.h
> @@ -155,7 +155,7 @@ enum binder_stat_types {
> };
>
> struct binder_stats {
> - atomic_t br[_IOC_NR(BR_FAILED_REPLY) + 1];
> + atomic_t br[_IOC_NR(BR_FROZEN_REPLY) + 1];
> atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1];
> atomic_t obj_created[BINDER_STAT_COUNT];
> atomic_t obj_deleted[BINDER_STAT_COUNT];
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 2/2] binder: tell userspace to dump current backtrace when detected oneway spamming
2021-04-09 9:40 ` [PATCH 2/2] binder: tell userspace to dump current backtrace when detected oneway spamming Hang Lu
@ 2021-04-09 15:16 ` Todd Kjos
0 siblings, 0 replies; 5+ messages in thread
From: Todd Kjos @ 2021-04-09 15:16 UTC (permalink / raw)
To: Hang Lu
Cc: Greg Kroah-Hartman, Todd Kjos, Martijn Coenen,
Arve Hjønnevåg, Joel Fernandes (Google),
Christian Brauner, Hridya Valsaraju, Suren Baghdasaryan, rdunlap,
LKML
On Fri, Apr 9, 2021 at 2:42 AM Hang Lu <hangl@codeaurora.org> wrote:
>
> When async binder buffer got exhausted, some normal oneway transactions
> will also be discarded and may cause system or application failures. By
> that time, the binder debug information we dump may not be relevant to
> the root cause. And this issue is difficult to debug if without the
> backtrace of the thread sending spam.
>
> This change will send BR_ONEWAY_SPAM_SUSPECT to userspace when oneway
> spamming is detected, request to dump current backtrace. Oneway spamming
> will be reported only once when exceeding the threshold (target process
> dips below 80% of its oneway space, and current process is responsible for
> either more than 50 transactions, or more than 50% of the oneway space).
> And the detection will restart when the async buffer has returned to a
> healthy state.
>
> Signed-off-by: Hang Lu <hangl@codeaurora.org>
Acked-by: Todd Kjos <tkjos@google.com>
> ---
> drivers/android/binder.c | 27 ++++++++++++++++++++++++---
> drivers/android/binder_alloc.c | 15 ++++++++++++---
> drivers/android/binder_alloc.h | 8 +++++++-
> drivers/android/binder_internal.h | 6 +++++-
> include/uapi/linux/android/binder.h | 8 ++++++++
> 5 files changed, 56 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index be34da3..63d2c43 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -3020,7 +3020,10 @@ static void binder_transaction(struct binder_proc *proc,
> goto err_bad_object_type;
> }
> }
> - tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
> + if (t->buffer->oneway_spam_suspect)
> + tcomplete->type = BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT;
> + else
> + tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
> t->work.type = BINDER_WORK_TRANSACTION;
>
> if (reply) {
> @@ -3893,9 +3896,14 @@ static int binder_thread_read(struct binder_proc *proc,
>
> binder_stat_br(proc, thread, cmd);
> } break;
> - case BINDER_WORK_TRANSACTION_COMPLETE: {
> + case BINDER_WORK_TRANSACTION_COMPLETE:
> + case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT: {
> + if (proc->oneway_spam_detection_enabled &&
> + w->type == BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT)
> + cmd = BR_ONEWAY_SPAM_SUSPECT;
> + else
> + cmd = BR_TRANSACTION_COMPLETE;
> binder_inner_proc_unlock(proc);
> - cmd = BR_TRANSACTION_COMPLETE;
> kfree(w);
> binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
> if (put_user(cmd, (uint32_t __user *)ptr))
> @@ -4897,6 +4905,18 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> }
> break;
> }
> + case BINDER_ENABLE_ONEWAY_SPAM_DETECTION: {
> + uint32_t enable;
> +
> + if (copy_from_user(&enable, ubuf, sizeof(enable))) {
> + ret = -EINVAL;
> + goto err;
> + }
> + binder_inner_proc_lock(proc);
> + proc->oneway_spam_detection_enabled = (bool)enable;
> + binder_inner_proc_unlock(proc);
> + break;
> + }
> default:
> ret = -EINVAL;
> goto err;
> @@ -5561,6 +5581,7 @@ static const char * const binder_return_strings[] = {
> "BR_CLEAR_DEATH_NOTIFICATION_DONE",
> "BR_FAILED_REPLY",
> "BR_FROZEN_REPLY",
> + "BR_ONEWAY_SPAM_SUSPECT",
> };
>
> static const char * const binder_command_strings[] = {
> diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
> index 7caf74a..340515f 100644
> --- a/drivers/android/binder_alloc.c
> +++ b/drivers/android/binder_alloc.c
> @@ -338,7 +338,7 @@ static inline struct vm_area_struct *binder_alloc_get_vma(
> return vma;
> }
>
> -static void debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
> +static bool debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
> {
> /*
> * Find the amount and size of buffers allocated by the current caller;
> @@ -366,13 +366,19 @@ static void debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
>
> /*
> * Warn if this pid has more than 50 transactions, or more than 50% of
> - * async space (which is 25% of total buffer size).
> + * async space (which is 25% of total buffer size). Oneway spam is only
> + * detected when the threshold is exceeded.
> */
> if (num_buffers > 50 || total_alloc_size > alloc->buffer_size / 4) {
> binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
> "%d: pid %d spamming oneway? %zd buffers allocated for a total size of %zd\n",
> alloc->pid, pid, num_buffers, total_alloc_size);
> + if (!alloc->oneway_spam_detected) {
> + alloc->oneway_spam_detected = true;
> + return true;
> + }
> }
> + return false;
> }
>
> static struct binder_buffer *binder_alloc_new_buf_locked(
> @@ -525,6 +531,7 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
> buffer->async_transaction = is_async;
> buffer->extra_buffers_size = extra_buffers_size;
> buffer->pid = pid;
> + buffer->oneway_spam_suspect = false;
> if (is_async) {
> alloc->free_async_space -= size + sizeof(struct binder_buffer);
> binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
> @@ -536,7 +543,9 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
> * of async space left (which is less than 10% of total
> * buffer size).
> */
> - debug_low_async_space_locked(alloc, pid);
> + buffer->oneway_spam_suspect = debug_low_async_space_locked(alloc, pid);
> + } else {
> + alloc->oneway_spam_detected = false;
> }
> }
> return buffer;
> diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h
> index 6e8e001..7dea57a 100644
> --- a/drivers/android/binder_alloc.h
> +++ b/drivers/android/binder_alloc.h
> @@ -26,6 +26,8 @@ struct binder_transaction;
> * @clear_on_free: %true if buffer must be zeroed after use
> * @allow_user_free: %true if user is allowed to free buffer
> * @async_transaction: %true if buffer is in use for an async txn
> + * @oneway_spam_suspect: %true if total async allocate size just exceed
> + * spamming detect threshold
> * @debug_id: unique ID for debugging
> * @transaction: pointer to associated struct binder_transaction
> * @target_node: struct binder_node associated with this buffer
> @@ -45,7 +47,8 @@ struct binder_buffer {
> unsigned clear_on_free:1;
> unsigned allow_user_free:1;
> unsigned async_transaction:1;
> - unsigned debug_id:28;
> + unsigned oneway_spam_suspect:1;
> + unsigned debug_id:27;
>
> struct binder_transaction *transaction;
>
> @@ -87,6 +90,8 @@ struct binder_lru_page {
> * @buffer_size: size of address space specified via mmap
> * @pid: pid for associated binder_proc (invariant after init)
> * @pages_high: high watermark of offset in @pages
> + * @oneway_spam_detected: %true if oneway spam detection fired, clear that
> + * flag once the async buffer has returned to a healthy state
> *
> * Bookkeeping structure for per-proc address space management for binder
> * buffers. It is normally initialized during binder_init() and binder_mmap()
> @@ -107,6 +112,7 @@ struct binder_alloc {
> uint32_t buffer_free;
> int pid;
> size_t pages_high;
> + bool oneway_spam_detected;
> };
>
> #ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST
> diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h
> index a507166..810c0b8 100644
> --- a/drivers/android/binder_internal.h
> +++ b/drivers/android/binder_internal.h
> @@ -155,7 +155,7 @@ enum binder_stat_types {
> };
>
> struct binder_stats {
> - atomic_t br[_IOC_NR(BR_FROZEN_REPLY) + 1];
> + atomic_t br[_IOC_NR(BR_ONEWAY_SPAM_SUSPECT) + 1];
> atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1];
> atomic_t obj_created[BINDER_STAT_COUNT];
> atomic_t obj_deleted[BINDER_STAT_COUNT];
> @@ -174,6 +174,7 @@ struct binder_work {
> enum binder_work_type {
> BINDER_WORK_TRANSACTION = 1,
> BINDER_WORK_TRANSACTION_COMPLETE,
> + BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT,
> BINDER_WORK_RETURN_ERROR,
> BINDER_WORK_NODE,
> BINDER_WORK_DEAD_BINDER,
> @@ -409,6 +410,8 @@ struct binder_ref {
> * @outer_lock: no nesting under innor or node lock
> * Lock order: 1) outer, 2) node, 3) inner
> * @binderfs_entry: process-specific binderfs log file
> + * @oneway_spam_detection_enabled: process enabled oneway spam detection
> + * or not
> *
> * Bookkeeping structure for binder processes
> */
> @@ -444,6 +447,7 @@ struct binder_proc {
> spinlock_t inner_lock;
> spinlock_t outer_lock;
> struct dentry *binderfs_entry;
> + bool oneway_spam_detection_enabled;
> };
>
> /**
> diff --git a/include/uapi/linux/android/binder.h b/include/uapi/linux/android/binder.h
> index 156070d..20e435f 100644
> --- a/include/uapi/linux/android/binder.h
> +++ b/include/uapi/linux/android/binder.h
> @@ -241,6 +241,7 @@ struct binder_frozen_status_info {
> #define BINDER_SET_CONTEXT_MGR_EXT _IOW('b', 13, struct flat_binder_object)
> #define BINDER_FREEZE _IOW('b', 14, struct binder_freeze_info)
> #define BINDER_GET_FROZEN_INFO _IOWR('b', 15, struct binder_frozen_status_info)
> +#define BINDER_ENABLE_ONEWAY_SPAM_DETECTION _IOW('b', 16, __u32)
>
> /*
> * NOTE: Two special error codes you should check for when calling
> @@ -428,6 +429,13 @@ enum binder_driver_return_protocol {
> * The target of the last transaction (either a bcTRANSACTION or
> * a bcATTEMPT_ACQUIRE) is frozen. No parameters.
> */
> +
> + BR_ONEWAY_SPAM_SUSPECT = _IO('r', 19),
> + /*
> + * Current process sent too many oneway calls to target, and the last
> + * asynchronous transaction makes the allocated async buffer size exceed
> + * detection threshold. No parameters.
> + */
> };
>
> enum binder_driver_command_protocol {
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-04-09 15:16 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-04-09 9:40 [PATCH 0/2] binder: tell userspace to dump current backtrace when detected oneway spamming Hang Lu
2021-04-09 9:40 ` [PATCH 1/2] binder: fix the missing BR_FROZEN_REPLY in binder_return_strings Hang Lu
2021-04-09 15:12 ` Todd Kjos
2021-04-09 9:40 ` [PATCH 2/2] binder: tell userspace to dump current backtrace when detected oneway spamming Hang Lu
2021-04-09 15:16 ` Todd Kjos
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