From 432ff1e91694e4c55a5bf6bc0574f4c254970232 Mon Sep 17 00:00:00 2001 From: Marco Ballesio Date: Mon, 15 Mar 2021 18:16:28 -0700 Subject: binder: BINDER_FREEZE ioctl Frozen tasks can't process binder transactions, so a way is required to inform transmitting ends of communication failures due to the frozen state of their receiving counterparts. Additionally, races are possible between transitions to frozen state and binder transactions enqueued to a specific process. Implement BINDER_FREEZE ioctl for user space to inform the binder driver about the intention to freeze or unfreeze a process. When the ioctl is called, block the caller until any pending binder transactions toward the target process are flushed. Return an error to transactions to processes marked as frozen. Co-developed-by: Todd Kjos Acked-by: Todd Kjos Signed-off-by: Marco Ballesio Signed-off-by: Todd Kjos Signed-off-by: Li Li Link: https://lore.kernel.org/r/20210316011630.1121213-2-dualli@chromium.org Signed-off-by: Greg Kroah-Hartman --- include/uapi/linux/android/binder.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include/uapi/linux/android') diff --git a/include/uapi/linux/android/binder.h b/include/uapi/linux/android/binder.h index ec84ad106568..7eb5b818b3c1 100644 --- a/include/uapi/linux/android/binder.h +++ b/include/uapi/linux/android/binder.h @@ -217,6 +217,12 @@ struct binder_node_info_for_ref { __u32 reserved3; }; +struct binder_freeze_info { + __u32 pid; + __u32 enable; + __u32 timeout_ms; +}; + #define BINDER_WRITE_READ _IOWR('b', 1, struct binder_write_read) #define BINDER_SET_IDLE_TIMEOUT _IOW('b', 3, __s64) #define BINDER_SET_MAX_THREADS _IOW('b', 5, __u32) @@ -227,6 +233,7 @@ struct binder_node_info_for_ref { #define BINDER_GET_NODE_DEBUG_INFO _IOWR('b', 11, struct binder_node_debug_info) #define BINDER_GET_NODE_INFO_FOR_REF _IOWR('b', 12, struct binder_node_info_for_ref) #define BINDER_SET_CONTEXT_MGR_EXT _IOW('b', 13, struct flat_binder_object) +#define BINDER_FREEZE _IOW('b', 14, struct binder_freeze_info) /* * NOTE: Two special error codes you should check for when calling @@ -408,6 +415,12 @@ enum binder_driver_return_protocol { * The last transaction (either a bcTRANSACTION or * a bcATTEMPT_ACQUIRE) failed (e.g. out of memory). No parameters. */ + + BR_FROZEN_REPLY = _IO('r', 18), + /* + * The target of the last transaction (either a bcTRANSACTION or + * a bcATTEMPT_ACQUIRE) is frozen. No parameters. + */ }; enum binder_driver_command_protocol { -- cgit v1.2.3 From ae28c1be1e54f2eda1c8b4469c4652e8a24056ed Mon Sep 17 00:00:00 2001 From: Marco Ballesio Date: Mon, 15 Mar 2021 18:16:30 -0700 Subject: binder: BINDER_GET_FROZEN_INFO ioctl User space needs to know if binder transactions occurred to frozen processes. Introduce a new BINDER_GET_FROZEN ioctl and keep track of transactions occurring to frozen proceses. Signed-off-by: Marco Ballesio Signed-off-by: Li Li Acked-by: Todd Kjos Link: https://lore.kernel.org/r/20210316011630.1121213-4-dualli@chromium.org Signed-off-by: Greg Kroah-Hartman --- include/uapi/linux/android/binder.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/uapi/linux/android') diff --git a/include/uapi/linux/android/binder.h b/include/uapi/linux/android/binder.h index 7eb5b818b3c1..156070d18c4f 100644 --- a/include/uapi/linux/android/binder.h +++ b/include/uapi/linux/android/binder.h @@ -223,6 +223,12 @@ struct binder_freeze_info { __u32 timeout_ms; }; +struct binder_frozen_status_info { + __u32 pid; + __u32 sync_recv; + __u32 async_recv; +}; + #define BINDER_WRITE_READ _IOWR('b', 1, struct binder_write_read) #define BINDER_SET_IDLE_TIMEOUT _IOW('b', 3, __s64) #define BINDER_SET_MAX_THREADS _IOW('b', 5, __u32) @@ -234,6 +240,7 @@ struct binder_freeze_info { #define BINDER_GET_NODE_INFO_FOR_REF _IOWR('b', 12, struct binder_node_info_for_ref) #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) /* * NOTE: Two special error codes you should check for when calling -- cgit v1.2.3 From a7dc1e6f99df59799ab0128d9c4e47bbeceb934d Mon Sep 17 00:00:00 2001 From: Hang Lu Date: Fri, 9 Apr 2021 17:40:46 +0800 Subject: binder: tell userspace to dump current backtrace when detected oneway spamming 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. Acked-by: Todd Kjos Signed-off-by: Hang Lu Link: https://lore.kernel.org/r/1617961246-4502-3-git-send-email-hangl@codeaurora.org Signed-off-by: Greg Kroah-Hartman --- include/uapi/linux/android/binder.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/uapi/linux/android') diff --git a/include/uapi/linux/android/binder.h b/include/uapi/linux/android/binder.h index 156070d18c4f..20e435fe657a 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 { -- cgit v1.2.3