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[34.125.197.132]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-b02a2d3a250sm8659543a12.62.2025.04.15.00.10.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Apr 2025 00:10:31 -0700 (PDT) From: Li Li To: dualli@google.com, corbet@lwn.net, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, donald.hunter@gmail.com, gregkh@linuxfoundation.org, arve@android.com, tkjos@android.com, maco@android.com, joel@joelfernandes.org, brauner@kernel.org, cmllamas@google.com, surenb@google.com, omosnace@redhat.com, shuah@kernel.org, arnd@arndb.de, masahiroy@kernel.org, bagasdotme@gmail.com, horms@kernel.org, tweek@google.com, paul@paul-moore.com, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, netdev@vger.kernel.org, selinux@vger.kernel.org, hridya@google.com Cc: smoreland@google.com, ynaffit@google.com, kernel-team@android.com Subject: [PATCH v17 2/3] binder: report txn errors via generic netlink Date: Tue, 15 Apr 2025 00:10:16 -0700 Message-ID: <20250415071017.3261009-3-dualli@chromium.org> X-Mailer: git-send-email 2.49.0.604.gff1f9ca942-goog In-Reply-To: <20250415071017.3261009-1-dualli@chromium.org> References: <20250415071017.3261009-1-dualli@chromium.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Li Li Introduce generic netlink messages into the binder driver so that the Linux/Android system administration processes can listen to important events and take corresponding actions, like stopping a broken app from attacking the OS by sending huge amount of spamming binder transactions. The binder netlink sources and headers are automatically generated from the corresponding binder netlink YAML spec. Don't modify them directly. Signed-off-by: Li Li --- Documentation/admin-guide/binder_netlink.rst | 108 ++++++++++ Documentation/admin-guide/index.rst | 1 + Documentation/netlink/specs/binder.yaml | 116 ++++++++++ drivers/android/Kconfig | 1 + drivers/android/Makefile | 2 +- drivers/android/binder.c | 215 ++++++++++++++++++- drivers/android/binder_internal.h | 16 ++ drivers/android/binder_netlink.c | 46 ++++ drivers/android/binder_netlink.h | 23 ++ drivers/android/binder_trace.h | 35 +++ include/uapi/linux/android/binder_netlink.h | 57 +++++ 11 files changed, 615 insertions(+), 5 deletions(-) create mode 100644 Documentation/admin-guide/binder_netlink.rst create mode 100644 Documentation/netlink/specs/binder.yaml create mode 100644 drivers/android/binder_netlink.c create mode 100644 drivers/android/binder_netlink.h create mode 100644 include/uapi/linux/android/binder_netlink.h diff --git a/Documentation/admin-guide/binder_netlink.rst b/Documentation/admin-guide/binder_netlink.rst new file mode 100644 index 000000000000..83f54f0d8c45 --- /dev/null +++ b/Documentation/admin-guide/binder_netlink.rst @@ -0,0 +1,108 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============================================================== +Generic Netlink for the Android Binder Driver (Binder Netlink) +============================================================== + +The Generic Netlink subsystem in the Linux kernel provides a generic way for +the Linux kernel to communicate with the user space applications via binder +driver. It is used to report binder transaction errors and warnings to user +space administration process. The driver allows multiple binder devices and +their corresponding binder contexts. Each context and their processes can be +configured independently to report their own transactions. + +Basically, the user space code uses the BINDER_CMD_REPORT_SETUP command to +request what kind of binder transactions should be reported by the driver. +The driver then echoes the attributes in a reply message to acknowledge the +request. The BINDER_CMD_REPORT_SETUP command also registers the current +user space process to receive the reports. This BINDER_CMD_REPORT_SETUP +command is protected by SELinux, to prevent unauthorized user apps from +triggering unexpected reports. + +Currently the driver reports these binder transaction errors and warnings. +1. "FAILED" transactions that fail to reach the target process; +2. "ASYNC_FROZEN" transactions that are delayed due to the target process +being frozen by cgroup freezer; or +3. "SPAM" transactions that are considered spamming according to existing +logic in binder_alloc.c. + +When the specified binder transactions happen, the driver uses the +BINDER_CMD_REPORT command to send a generic netlink message to the +registered process, containing the payload defined in binder.yaml. + +More details about the flags, attributes and operations can be found at the +the doc sections in Documentations/netlink/specs/binder.yaml and the +kernel-doc comments of the new source code in binder.{h|c}. + +Using Binder Netlink +-------------------- + +The Binder Netlink can be used in the same way as any other generic netlink +drivers. Userspace application uses a raw netlink socket to send commands +to and receive packets from the kernel driver. + +Usage example (user space pseudo code): + +:: + /* + * send() below is overloaded to pack netlink commands and attributes + * to nlattr/genlmsghdr/nlmsghdr and then send to the netlink socket. + * + * recv() below is overloaded to receive the raw netlink message from + * the netlink socket, parse nlmsghdr/genlmsghdr to find the netlink + * command and then return the nlattr payload. + */ + + // open netlink socket + int fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); + + // bind netlink socket + bind(fd, struct socketaddr); + + // get the family id of the binder netlink + send(fd, CTRL_CMD_GETFAMILY, CTRL_ATTR_FAMILY_NAME, + BINDER_FAMILY_NAME); + void *data = recv(CTRL_CMD_NEWFAMILY); + if (!has_nla_type(data, CTRL_ATTR_FAMILY_ID)) { + // Binder Netlink isn't available on this version of Linux kernel + return; + } + __u16 id = nla(data)[CTRL_ATTR_FAMILY_ID]; + __u32 grp = nla(data)[CTRL_ATTR_MCAST_GROUPS][CTRL_ATTR_MCAST_GRP_ID]; + + // join the mcast group to listen to the binder netlink messages + setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &grp, sizeof(grp)); + + // enable per-context binder report + send(fd, id, BINDER_CMD_REPORT_SETUP, "binder", 0, + BINDER_FLAG_FAILED | BINDER_FLAG_DELAYED); + + // confirm the per-context configuration + data = recv(fd, BINDER_CMD_REPLY); + char *context = nla(data)[BINDER_A_CMD_CONTEXT]; + __u32 pid = nla(data)[BINDER_A_CMD_PID]; + __u32 flags = nla(data)[BINDER_A_CMD_FLAGS]; + + // set optional per-process report, overriding the per-context one + send(fd, id, BINDER_CMD_REPORT_SETUP, "binder", getpid(), + BINDER_FLAG_SPAM | BINDER_REPORT_OVERRIDE); + + // confirm the optional per-process configuration + data = recv(fd, BINDER_CMD_REPLY); + context = nla(data)[BINDER_A_CMD_CONTEXT]; + pid = nla(data)[BINDER_A_CMD_PID]; + flags = nla(data)[BINDER_A_CMD_FLAGS]; + + // wait and read all binder reports + while (running) { + data = recv(fd, BINDER_CMD_REPORT); + auto *attr = nla(data)[BINDER_A_REPORT_XXX]; + + // process binder report + do_something(*attr); + } + + // clean up + send(fd, id, BINDER_CMD_REPORT_SETUP, 0, 0); + send(fd, id, BINDER_CMD_REPORT_SETUP, getpid(), 0); + close(fd); diff --git a/Documentation/admin-guide/index.rst b/Documentation/admin-guide/index.rst index 259d79fbeb94..c7d4357ed3e6 100644 --- a/Documentation/admin-guide/index.rst +++ b/Documentation/admin-guide/index.rst @@ -120,6 +120,7 @@ Block-layer and filesystem administration :maxdepth: 1 bcache + binder_netlink binderfs blockdev/index cifs/index diff --git a/Documentation/netlink/specs/binder.yaml b/Documentation/netlink/specs/binder.yaml new file mode 100644 index 000000000000..e184645f6c41 --- /dev/null +++ b/Documentation/netlink/specs/binder.yaml @@ -0,0 +1,116 @@ +# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) + +name: binder +protocol: genetlink +uapi-header: linux/android/binder_netlink.h +doc: Netlink protocol to report binder transaction errors and warnings. + +definitions: + - + type: flags + name: flag + doc: Define what kind of binder transactions should be reported. + entries: [ failed, async-frozen, spam, override ] + +attribute-sets: + - + name: cmd + doc: The supported attributes of "report-setup" command. + attributes: + - + name: context + type: string + doc: The binder context to enable binder netlink report. + - + name: pid + type: u32 + doc: The binder proc to enable binder netlink report. + - + name: flags + type: u32 + enum: flag + doc: What kind of binder transactions should be reported. + - + name: report + doc: The supported attributes of "report" command + attributes: + - + name: context + type: string + doc: The binder context where the binder netlink report happens. + - + name: err + type: u32 + doc: Copy of binder_driver_return_protocol returned to the sender. + - + name: from_pid + type: u32 + doc: Sender pid of the corresponding binder transaction. + - + name: from_tid + type: u32 + doc: Sender tid of the corresponding binder transaction. + - + name: to_pid + type: u32 + doc: Target pid of the corresponding binder transaction. + - + name: to_tid + type: u32 + doc: Target tid of the corresponding binder transaction. + - + name: reply + type: u32 + doc: 1 means the transaction is a reply, 0 otherwise. + - + name: flags + type: u32 + doc: Copy of binder_transaction_data->flags. + - + name: code + type: u32 + doc: Copy of binder_transaction_data->code. + - + name: data_size + type: u32 + doc: Copy of binder_transaction_data->data_size. + +operations: + list: + - + name: report-setup + doc: Set flags from user space. + attribute-set: cmd + + do: + request: ¶ms + attributes: + - context + - pid + - flags + reply: *params + - + name: report + doc: Send the requested reports to user space. + attribute-set: report + + event: + attributes: + - context + - err + - from_pid + - from_tid + - to_pid + - to_tid + - reply + - flags + - code + - data_size + +kernel-family: + headers: [ "binder_internal.h" ] + +mcast-groups: + list: + - + name: report diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig index 07aa8ae0a058..e2fa620934e2 100644 --- a/drivers/android/Kconfig +++ b/drivers/android/Kconfig @@ -4,6 +4,7 @@ menu "Android" config ANDROID_BINDER_IPC bool "Android Binder IPC Driver" depends on MMU + depends on NET default n help Binder is used in Android for both communication between processes, diff --git a/drivers/android/Makefile b/drivers/android/Makefile index c9d3d0c99c25..b8874dba884e 100644 --- a/drivers/android/Makefile +++ b/drivers/android/Makefile @@ -2,5 +2,5 @@ ccflags-y += -I$(src) # needed for trace events obj-$(CONFIG_ANDROID_BINDERFS) += binderfs.o -obj-$(CONFIG_ANDROID_BINDER_IPC) += binder.o binder_alloc.o +obj-$(CONFIG_ANDROID_BINDER_IPC) += binder.o binder_alloc.o binder_netlink.o obj-$(CONFIG_ANDROID_BINDER_IPC_SELFTEST) += binder_alloc_selftest.o diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 76052006bd87..22ec08d9995d 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -72,6 +72,7 @@ #include +#include "binder_netlink.h" #include "binder_internal.h" #include "binder_trace.h" @@ -2990,6 +2991,86 @@ static void binder_set_txn_from_error(struct binder_transaction *t, int id, binder_thread_dec_tmpref(from); } +/** + * binder_netlink_enabled() - check if binder netlink reports are enabled + * @proc: the binder_proc to check + * @mask: the categories of binder netlink reports + * + * Returns true if certain binder netlink reports are enabled for this binder + * proc (when per-process overriding takes effect) or context. + */ +static bool binder_netlink_enabled(struct binder_proc *proc, u32 mask) +{ + struct binder_context *context = proc->context; + + if (!genl_has_listeners(&binder_nl_family, &init_net, BINDER_NLGRP_REPORT)) + return false; + + if (proc->report_flags & BINDER_FLAG_OVERRIDE) + return (proc->report_flags & mask) != 0; + else + return (context->report_flags & mask) != 0; +} + +/** + * binder_netlink_report() - report one binder netlink event + * @context: the binder context + * @err: copy of binder_driver_return_protocol returned to the sender + * @reply: whether the binder transaction is a reply + * @t: the binder transaction + * + * Packs the report data into a binder netlink message and send it. + */ +static void binder_netlink_report(struct binder_context *context, u32 err, + u32 reply, struct binder_transaction *t) +{ + struct sk_buff *skb; + void *hdr; + int ret; + + trace_binder_netlink_report(context->name, err, reply, t); + + skb = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!skb) { + pr_err("Failed to alloc binder netlink message\n"); + return; + } + + hdr = genlmsg_put(skb, 0, atomic_inc_return(&context->report_seq), + &binder_nl_family, 0, BINDER_CMD_REPORT); + if (!hdr) + goto free_skb; + + if (nla_put_string(skb, BINDER_A_REPORT_CONTEXT, context->name) || + nla_put_u32(skb, BINDER_A_REPORT_ERR, err) || + nla_put_u32(skb, BINDER_A_REPORT_FROM_PID, t->from_pid) || + nla_put_u32(skb, BINDER_A_REPORT_FROM_TID, t->from_tid) || + nla_put_u32(skb, BINDER_A_REPORT_TO_PID, + t->to_proc ? t->to_proc->pid : 0) || + nla_put_u32(skb, BINDER_A_REPORT_TO_TID, + t->to_thread ? t->to_thread->pid : 0) || + nla_put_u32(skb, BINDER_A_REPORT_REPLY, reply) || + nla_put_u32(skb, BINDER_A_REPORT_FLAGS, t->flags) || + nla_put_u32(skb, BINDER_A_REPORT_CODE, t->code) || + nla_put_u32(skb, BINDER_A_REPORT_DATA_SIZE, t->buffer->data_size)) + goto cancel_skb; + + genlmsg_end(skb, hdr); + + ret = genlmsg_multicast(&binder_nl_family, skb, 0, BINDER_NLGRP_REPORT, GFP_KERNEL); + if (ret < 0) + pr_err("Failed to send binder netlink message: %d\n", ret); + + return; + +cancel_skb: + pr_err("Failed to add attributes to binder netlink message\n"); + genlmsg_cancel(skb, hdr); +free_skb: + pr_err("Free binder netlink report message on error\n"); + nlmsg_free(skb); +} + static void binder_transaction(struct binder_proc *proc, struct binder_thread *thread, struct binder_transaction_data *tr, int reply, @@ -3683,10 +3764,14 @@ static void binder_transaction(struct binder_proc *proc, return_error_line = __LINE__; goto err_copy_data_failed; } - if (t->buffer->oneway_spam_suspect) + if (t->buffer->oneway_spam_suspect) { tcomplete->type = BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT; - else + if (binder_netlink_enabled(proc, BINDER_FLAG_SPAM)) + binder_netlink_report(context, BR_ONEWAY_SPAM_SUSPECT, + reply, t); + } else { tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE; + } t->work.type = BINDER_WORK_TRANSACTION; if (reply) { @@ -3736,8 +3821,12 @@ static void binder_transaction(struct binder_proc *proc, * process and is put in a pending queue, waiting for the target * process to be unfrozen. */ - if (return_error == BR_TRANSACTION_PENDING_FROZEN) + if (return_error == BR_TRANSACTION_PENDING_FROZEN) { tcomplete->type = BINDER_WORK_TRANSACTION_PENDING; + if (binder_netlink_enabled(proc, BINDER_FLAG_ASYNC_FROZEN)) + binder_netlink_report(context, return_error, + reply, t); + } binder_enqueue_thread_work(thread, tcomplete); if (return_error && return_error != BR_TRANSACTION_PENDING_FROZEN) @@ -3799,6 +3888,10 @@ static void binder_transaction(struct binder_proc *proc, binder_dec_node_tmpref(target_node); } + if (binder_netlink_enabled(proc, BINDER_FLAG_FAILED)) + binder_netlink_report(context, return_error, + reply, t); + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, "%d:%d transaction %s to %d:%d failed %d/%d/%d, code %u size %lld-%lld line %d\n", proc->pid, thread->pid, reply ? "reply" : @@ -6334,6 +6427,113 @@ binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer) mutex_unlock(&binder_deferred_lock); } +/** + * binder_nl_report_setup_doit() - netlink .doit handler + * @skb: the metadata struct passed from netlink driver + * @info: the generic netlink struct passed from netlink driver + * + * Implements the .doit function to process binder netlink commands. + */ +int binder_nl_report_setup_doit(struct sk_buff *skb, struct genl_info *info) +{ + struct binder_context *context = NULL; + struct binder_device *device; + struct binder_proc *proc; + u32 flags, pid; + bool found; + void *hdr; + int ret; + + ret = security_binder_setup_report(current_cred()); + if (ret < 0) { + NL_SET_ERR_MSG(info->extack, "Permission denied"); + return ret; + } + + if (nla_len(info->attrs[BINDER_A_CMD_CONTEXT])) { + /* Search the specified binder context */ + hlist_for_each_entry(device, &binder_devices, hlist) { + if (!nla_strcmp(info->attrs[BINDER_A_CMD_CONTEXT], + device->context.name)) { + context = &device->context; + break; + } + } + + if (!context) { + NL_SET_ERR_MSG(info->extack, "Invalid binder context"); + return -EINVAL; + } + } + + pid = nla_get_u32(info->attrs[BINDER_A_CMD_PID]); + flags = nla_get_u32(info->attrs[BINDER_A_CMD_FLAGS]); + + if (!pid) { + if (!context) { + NL_SET_ERR_MSG(info->extack, + "Invalid binder context and pid"); + return -EINVAL; + } + + /* Set the global flags for the whole binder context */ + context->report_flags = flags; + } else { + /* Set the per-process flags */ + found = false; + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(proc, &binder_procs, proc_node) { + if (proc->pid == pid + && (proc->context == context || !context)) { + proc->report_flags = flags; + found = true; + } + } + mutex_unlock(&binder_procs_lock); + + if (!found) { + NL_SET_ERR_MSG_FMT(info->extack, + "Invalid binder report pid %u", + pid); + return -EINVAL; + } + } + + skb = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!skb) { + pr_err("Failed to alloc binder netlink reply message\n"); + return -ENOMEM; + } + + hdr = genlmsg_iput(skb, info); + if (!hdr) + goto free_skb; + + if (nla_put_string(skb, BINDER_A_CMD_CONTEXT, context->name) || + nla_put_u32(skb, BINDER_A_CMD_PID, pid) || + nla_put_u32(skb, BINDER_A_CMD_FLAGS, flags)) + goto cancel_skb; + + genlmsg_end(skb, hdr); + + if (genlmsg_reply(skb, info)) { + pr_err("Failed to send binder netlink reply message\n"); + return -EFAULT; + } + + return 0; + +cancel_skb: + pr_err("Failed to add reply attributes to binder netlink message\n"); + genlmsg_cancel(skb, hdr); +free_skb: + pr_err("Free binder netlink reply message on error\n"); + nlmsg_free(skb); + ret = -EMSGSIZE; + + return ret; +} + static void print_binder_transaction_ilocked(struct seq_file *m, struct binder_proc *proc, const char *prefix, @@ -7009,12 +7209,19 @@ static int __init binder_init(void) } } - ret = init_binderfs(); + ret = genl_register_family(&binder_nl_family); if (ret) goto err_init_binder_device_failed; + ret = init_binderfs(); + if (ret) + goto err_init_binderfs_failed; + return ret; +err_init_binderfs_failed: + genl_unregister_family(&binder_nl_family); + err_init_binder_device_failed: hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) { misc_deregister(&device->miscdev); diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h index 6a66c9769c6c..8ddd1ddea8e0 100644 --- a/drivers/android/binder_internal.h +++ b/drivers/android/binder_internal.h @@ -11,15 +11,28 @@ #include #include #include +#include #include #include "binder_alloc.h" #include "dbitmap.h" +/** + * struct binder_context - information about a binder domain + * @binder_context_mgr_node: the context manager + * @context_mgr_node_lock: the lock protecting the above context manager node + * @binder_context_mgr_uid: the uid of the above context manager + * @name: the name of the binder device + * @report_flags: the categories of binder transactions that would + * be reported (see enum binder_report_flag). + * @report_seq: the seq number of the generic netlink report + */ struct binder_context { struct binder_node *binder_context_mgr_node; struct mutex context_mgr_node_lock; kuid_t binder_context_mgr_uid; const char *name; + u32 report_flags; + atomic_t report_seq; }; /** @@ -413,6 +426,8 @@ struct binder_ref { * @binderfs_entry: process-specific binderfs log file * @oneway_spam_detection_enabled: process enabled oneway spam detection * or not + * @report_flags: the categories of binder transactions that would + * be reported (see enum binder_genl_flag). * * Bookkeeping structure for binder processes */ @@ -451,6 +466,7 @@ struct binder_proc { spinlock_t outer_lock; struct dentry *binderfs_entry; bool oneway_spam_detection_enabled; + u32 report_flags; }; /** diff --git a/drivers/android/binder_netlink.c b/drivers/android/binder_netlink.c new file mode 100644 index 000000000000..9dc1820951c3 --- /dev/null +++ b/drivers/android/binder_netlink.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/binder.yaml */ +/* YNL-GEN kernel source */ + +#include +#include + +#include "binder_netlink.h" + +#include +#include + +/* BINDER_CMD_REPORT_SETUP - do */ +static const struct nla_policy binder_report_setup_nl_policy[BINDER_A_CMD_FLAGS + 1] = { + [BINDER_A_CMD_CONTEXT] = { .type = NLA_NUL_STRING, }, + [BINDER_A_CMD_PID] = { .type = NLA_U32, }, + [BINDER_A_CMD_FLAGS] = NLA_POLICY_MASK(NLA_U32, 0xf), +}; + +/* Ops table for binder */ +static const struct genl_split_ops binder_nl_ops[] = { + { + .cmd = BINDER_CMD_REPORT_SETUP, + .doit = binder_nl_report_setup_doit, + .policy = binder_report_setup_nl_policy, + .maxattr = BINDER_A_CMD_FLAGS, + .flags = GENL_CMD_CAP_DO, + }, +}; + +static const struct genl_multicast_group binder_nl_mcgrps[] = { + [BINDER_NLGRP_REPORT] = { "report", }, +}; + +struct genl_family binder_nl_family __ro_after_init = { + .name = BINDER_FAMILY_NAME, + .version = BINDER_FAMILY_VERSION, + .netnsok = true, + .parallel_ops = true, + .module = THIS_MODULE, + .split_ops = binder_nl_ops, + .n_split_ops = ARRAY_SIZE(binder_nl_ops), + .mcgrps = binder_nl_mcgrps, + .n_mcgrps = ARRAY_SIZE(binder_nl_mcgrps), +}; diff --git a/drivers/android/binder_netlink.h b/drivers/android/binder_netlink.h new file mode 100644 index 000000000000..0ef8c91ab319 --- /dev/null +++ b/drivers/android/binder_netlink.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */ +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/binder.yaml */ +/* YNL-GEN kernel header */ + +#ifndef _LINUX_BINDER_GEN_H +#define _LINUX_BINDER_GEN_H + +#include +#include + +#include +#include + +int binder_nl_report_setup_doit(struct sk_buff *skb, struct genl_info *info); + +enum { + BINDER_NLGRP_REPORT, +}; + +extern struct genl_family binder_nl_family; + +#endif /* _LINUX_BINDER_GEN_H */ diff --git a/drivers/android/binder_trace.h b/drivers/android/binder_trace.h index 16de1b9e72f7..968f14f029eb 100644 --- a/drivers/android/binder_trace.h +++ b/drivers/android/binder_trace.h @@ -423,6 +423,41 @@ TRACE_EVENT(binder_return, "unknown") ); +TRACE_EVENT(binder_netlink_report, + TP_PROTO(const char *name, u32 err, u32 reply, + struct binder_transaction *t), + TP_ARGS(name, err, reply, t), + TP_STRUCT__entry( + __field(const char *, name) + __field(u32, err) + __field(u32, from_pid) + __field(u32, from_tid) + __field(u32, to_pid) + __field(u32, to_tid) + __field(u32, reply) + __field(u32, flags) + __field(u32, code) + __field(binder_size_t, data_size) + ), + TP_fast_assign( + __entry->name = name; + __entry->err = err; + __entry->from_pid = t->from_pid; + __entry->from_tid = t->from_tid; + __entry->to_pid = t->to_proc ? t->to_proc->pid : 0; + __entry->to_tid = t->to_thread ? t->to_thread->pid : 0; + __entry->reply = reply; + __entry->flags = t->flags; + __entry->code = t->code; + __entry->data_size = t->buffer->data_size; + ), + TP_printk("%s: %d %d:%d -> %d:%d %s flags=0x08%x code=%d %llu", + __entry->name, __entry->err, __entry->from_pid, + __entry->from_tid, __entry->to_pid, __entry->to_tid, + __entry->reply ? "reply" : "", __entry->flags, + __entry->code, __entry->data_size) +); + #endif /* _BINDER_TRACE_H */ #undef TRACE_INCLUDE_PATH diff --git a/include/uapi/linux/android/binder_netlink.h b/include/uapi/linux/android/binder_netlink.h new file mode 100644 index 000000000000..fa926ed19507 --- /dev/null +++ b/include/uapi/linux/android/binder_netlink.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */ +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/binder.yaml */ +/* YNL-GEN uapi header */ + +#ifndef _UAPI_LINUX_ANDROID_BINDER_NETLINK_H +#define _UAPI_LINUX_ANDROID_BINDER_NETLINK_H + +#define BINDER_FAMILY_NAME "binder" +#define BINDER_FAMILY_VERSION 1 + +/* + * Define what kind of binder transactions should be reported. + */ +enum binder_flag { + BINDER_FLAG_FAILED = 1, + BINDER_FLAG_ASYNC_FROZEN = 2, + BINDER_FLAG_SPAM = 4, + BINDER_FLAG_OVERRIDE = 8, +}; + +enum { + BINDER_A_CMD_CONTEXT = 1, + BINDER_A_CMD_PID, + BINDER_A_CMD_FLAGS, + + __BINDER_A_CMD_MAX, + BINDER_A_CMD_MAX = (__BINDER_A_CMD_MAX - 1) +}; + +enum { + BINDER_A_REPORT_CONTEXT = 1, + BINDER_A_REPORT_ERR, + BINDER_A_REPORT_FROM_PID, + BINDER_A_REPORT_FROM_TID, + BINDER_A_REPORT_TO_PID, + BINDER_A_REPORT_TO_TID, + BINDER_A_REPORT_REPLY, + BINDER_A_REPORT_FLAGS, + BINDER_A_REPORT_CODE, + BINDER_A_REPORT_DATA_SIZE, + + __BINDER_A_REPORT_MAX, + BINDER_A_REPORT_MAX = (__BINDER_A_REPORT_MAX - 1) +}; + +enum { + BINDER_CMD_REPORT_SETUP = 1, + BINDER_CMD_REPORT, + + __BINDER_CMD_MAX, + BINDER_CMD_MAX = (__BINDER_CMD_MAX - 1) +}; + +#define BINDER_MCGRP_REPORT "report" + +#endif /* _UAPI_LINUX_ANDROID_BINDER_NETLINK_H */