From ac965d7d88fc36fb42e3d50225c0a44dd8326da4 Mon Sep 17 00:00:00 2001 From: "Masami Hiramatsu (Google)" Date: Wed, 26 Feb 2025 15:18:46 +0900 Subject: tracing: tprobe-events: Fix a memory leak when tprobe with $retval Fix a memory leak when a tprobe is defined with $retval. This combination is not allowed, but the parse_symbol_and_return() does not free the *symbol which should not be used if it returns the error. Thus, it leaks the *symbol memory in that error path. Link: https://lore.kernel.org/all/174055072650.4079315.3063014346697447838.stgit@mhiramat.tok.corp.google.com/ Fixes: ce51e6153f77 ("tracing: fprobe-event: Fix to check tracepoint event and return") Signed-off-by: Masami Hiramatsu (Google) Reviewed-by: Steven Rostedt (Google) Cc: stable@vger.kernel.org --- kernel/trace/trace_fprobe.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index b8f3c4ba309b..8826f44f69a4 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -1056,6 +1056,8 @@ static int parse_symbol_and_return(int argc, const char *argv[], if (is_tracepoint) { trace_probe_log_set_index(i); trace_probe_log_err(tmp - argv[i], RETVAL_ON_PROBE); + kfree(*symbol); + *symbol = NULL; return -EINVAL; } *is_return = true; -- cgit v1.2.3 From d0453655b6ddc685a4837f3cc0776ae8eef62d01 Mon Sep 17 00:00:00 2001 From: "Masami Hiramatsu (Google)" Date: Wed, 26 Feb 2025 15:18:54 +0900 Subject: tracing: tprobe-events: Reject invalid tracepoint name Commit 57a7e6de9e30 ("tracing/fprobe: Support raw tracepoints on future loaded modules") allows user to set a tprobe on non-exist tracepoint but it does not check the tracepoint name is acceptable. So it leads tprobe has a wrong character for events (e.g. with subsystem prefix). In this case, the event is not shown in the events directory. Reject such invalid tracepoint name. The tracepoint name must consist of alphabet or digit or '_'. Link: https://lore.kernel.org/all/174055073461.4079315.15875502830565214255.stgit@mhiramat.tok.corp.google.com/ Fixes: 57a7e6de9e30 ("tracing/fprobe: Support raw tracepoints on future loaded modules") Signed-off-by: Masami Hiramatsu (Google) Reviewed-by: Steven Rostedt (Google) Cc: stable@vger.kernel.org --- kernel/trace/trace_fprobe.c | 13 +++++++++++++ kernel/trace/trace_probe.h | 1 + 2 files changed, 14 insertions(+) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 8826f44f69a4..85f037dc1462 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -1049,6 +1049,19 @@ static int parse_symbol_and_return(int argc, const char *argv[], if (*is_return) return 0; + if (is_tracepoint) { + tmp = *symbol; + while (*tmp && (isalnum(*tmp) || *tmp == '_')) + tmp++; + if (*tmp) { + /* find a wrong character. */ + trace_probe_log_err(tmp - *symbol, BAD_TP_NAME); + kfree(*symbol); + *symbol = NULL; + return -EINVAL; + } + } + /* If there is $retval, this should be a return fprobe. */ for (i = 2; i < argc; i++) { tmp = strstr(argv[i], "$retval"); diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 5803e6a41570..fba3ede87054 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -481,6 +481,7 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(NON_UNIQ_SYMBOL, "The symbol is not unique"), \ C(BAD_RETPROBE, "Retprobe address must be an function entry"), \ C(NO_TRACEPOINT, "Tracepoint is not found"), \ + C(BAD_TP_NAME, "Invalid character in tracepoint name"),\ C(BAD_ADDR_SUFFIX, "Invalid probed address suffix"), \ C(NO_GROUP_NAME, "Group name is not specified"), \ C(GROUP_TOO_LONG, "Group name is too long"), \ -- cgit v1.2.3 From db5e228611b118cf7b1f8084063feda5c037f4a7 Mon Sep 17 00:00:00 2001 From: "Masami Hiramatsu (Google)" Date: Wed, 26 Feb 2025 15:19:02 +0900 Subject: tracing: fprobe-events: Log error for exceeding the number of entry args Add error message when the number of entry argument exceeds the maximum size of entry data. This is currently checked when registering fprobe, but in this case no error message is shown in the error_log file. Link: https://lore.kernel.org/all/174055074269.4079315.17809232650360988538.stgit@mhiramat.tok.corp.google.com/ Fixes: 25f00e40ce79 ("tracing/probes: Support $argN in return probe (kprobe and fprobe)") Signed-off-by: Masami Hiramatsu (Google) Reviewed-by: Steven Rostedt (Google) --- kernel/trace/trace_fprobe.c | 5 +++++ kernel/trace/trace_probe.h | 3 ++- 2 files changed, 7 insertions(+), 1 deletion(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 85f037dc1462..e27305d31fc5 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -1230,6 +1230,11 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], if (is_return && tf->tp.entry_arg) { tf->fp.entry_handler = trace_fprobe_entry_handler; tf->fp.entry_data_size = traceprobe_get_entry_data_size(&tf->tp); + if (ALIGN(tf->fp.entry_data_size, sizeof(long)) > MAX_FPROBE_DATA_SIZE) { + trace_probe_log_set_index(2); + trace_probe_log_err(0, TOO_MANY_EARGS); + return -E2BIG; + } } ret = traceprobe_set_print_fmt(&tf->tp, diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index fba3ede87054..c47ca002347a 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -545,7 +545,8 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(NO_BTF_FIELD, "This field is not found."), \ C(BAD_BTF_TID, "Failed to get BTF type info."),\ C(BAD_TYPE4STR, "This type does not fit for string."),\ - C(NEED_STRING_TYPE, "$comm and immediate-string only accepts string type"), + C(NEED_STRING_TYPE, "$comm and immediate-string only accepts string type"),\ + C(TOO_MANY_EARGS, "Too many entry arguments specified"), #undef C #define C(a, b) TP_ERR_##a -- cgit v1.2.3 From fd5ba38390c59e1c147480ae49b6133c4ac24001 Mon Sep 17 00:00:00 2001 From: "Masami Hiramatsu (Google)" Date: Wed, 26 Feb 2025 15:19:18 +0900 Subject: tracing: probe-events: Remove unused MAX_ARG_BUF_LEN macro Commit 18b1e870a496 ("tracing/probes: Add $arg* meta argument for all function args") introduced MAX_ARG_BUF_LEN but it is not used. Remove it. Link: https://lore.kernel.org/all/174055075876.4079315.8805416872155957588.stgit@mhiramat.tok.corp.google.com/ Fixes: 18b1e870a496 ("tracing/probes: Add $arg* meta argument for all function args") Signed-off-by: Masami Hiramatsu (Google) Reviewed-by: Steven Rostedt (Google) --- kernel/trace/trace_probe.h | 1 - 1 file changed, 1 deletion(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index c47ca002347a..96792bc4b092 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -36,7 +36,6 @@ #define MAX_BTF_ARGS_LEN 128 #define MAX_DENTRY_ARGS_LEN 256 #define MAX_STRING_SIZE PATH_MAX -#define MAX_ARG_BUF_LEN (MAX_TRACE_ARGS * MAX_ARG_NAME_LEN) /* Reserved field names */ #define FIELD_STRING_IP "__probe_ip" -- cgit v1.2.3 From 0b4ffbe4888a2c71185eaf5c1a02dd3586a9bc04 Mon Sep 17 00:00:00 2001 From: Tengda Wu Date: Fri, 14 Mar 2025 06:53:35 +0000 Subject: tracing: Correct the refcount if the hist/hist_debug file fails to open The function event_{hist,hist_debug}_open() maintains the refcount of 'file->tr' and 'file' through tracing_open_file_tr(). However, it does not roll back these counts on subsequent failure paths, resulting in a refcount leak. A very obvious case is that if the hist/hist_debug file belongs to a specific instance, the refcount leak will prevent the deletion of that instance, as it relies on the condition 'tr->ref == 1' within __remove_instance(). Fix this by calling tracing_release_file_tr() on all failure paths in event_{hist,hist_debug}_open() to correct the refcount. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Zheng Yejian Link: https://lore.kernel.org/20250314065335.1202817-1-wutengda@huaweicloud.com Fixes: 1cc111b9cddc ("tracing: Fix uaf issue when open the hist or hist_debug file") Signed-off-by: Tengda Wu Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_hist.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index ad7419e24055..53dc6719181e 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -5689,12 +5689,16 @@ static int event_hist_open(struct inode *inode, struct file *file) guard(mutex)(&event_mutex); event_file = event_file_data(file); - if (!event_file) - return -ENODEV; + if (!event_file) { + ret = -ENODEV; + goto err; + } hist_file = kzalloc(sizeof(*hist_file), GFP_KERNEL); - if (!hist_file) - return -ENOMEM; + if (!hist_file) { + ret = -ENOMEM; + goto err; + } hist_file->file = file; hist_file->last_act = get_hist_hit_count(event_file); @@ -5702,9 +5706,14 @@ static int event_hist_open(struct inode *inode, struct file *file) /* Clear private_data to avoid warning in single_open() */ file->private_data = NULL; ret = single_open(file, hist_show, hist_file); - if (ret) + if (ret) { kfree(hist_file); + goto err; + } + return 0; +err: + tracing_release_file_tr(inode, file); return ret; } @@ -5979,7 +5988,10 @@ static int event_hist_debug_open(struct inode *inode, struct file *file) /* Clear private_data to avoid warning in single_open() */ file->private_data = NULL; - return single_open(file, hist_debug_show, file); + ret = single_open(file, hist_debug_show, file); + if (ret) + tracing_release_file_tr(inode, file); + return ret; } const struct file_operations event_hist_debug_fops = { -- cgit v1.2.3