From 9da73974eb9c965dd9989befb593b8c8da9e4bdc Mon Sep 17 00:00:00 2001 From: Vamshi K Sthambamkadi Date: Wed, 22 Apr 2020 11:45:06 +0530 Subject: tracing: Fix memory leaks in trace_events_hist.c kmemleak report 1: [<9092c50b>] kmem_cache_alloc_trace+0x138/0x270 [<05a2c9ed>] create_field_var+0xcf/0x180 [<528a2d68>] action_create+0xe2/0xc80 [<63f50b61>] event_hist_trigger_func+0x15b5/0x1920 [<28ea5d3d>] trigger_process_regex+0x7b/0xc0 [<3138e86f>] event_trigger_write+0x4d/0xb0 [] __vfs_write+0x30/0x200 [<4f424a0d>] vfs_write+0x96/0x1b0 [] ksys_write+0x53/0xc0 [<3717101a>] __ia32_sys_write+0x15/0x20 [] do_fast_syscall_32+0x70/0x250 [<46e2629c>] entry_SYSENTER_32+0xaf/0x102 This is because save_vars[] of struct hist_trigger_data are not destroyed kmemleak report 2: [<9092c50b>] kmem_cache_alloc_trace+0x138/0x270 [<6e5e97c5>] create_var+0x3c/0x110 [] create_field_var+0xaf/0x180 [<528a2d68>] action_create+0xe2/0xc80 [<63f50b61>] event_hist_trigger_func+0x15b5/0x1920 [<28ea5d3d>] trigger_process_regex+0x7b/0xc0 [<3138e86f>] event_trigger_write+0x4d/0xb0 [] __vfs_write+0x30/0x200 [<4f424a0d>] vfs_write+0x96/0x1b0 [] ksys_write+0x53/0xc0 [<3717101a>] __ia32_sys_write+0x15/0x20 [] do_fast_syscall_32+0x70/0x250 [<46e2629c>] entry_SYSENTER_32+0xaf/0x102 struct hist_field allocated through create_var() do not initialize "ref" field to 1. The code in __destroy_hist_field() does not destroy object if "ref" is initialized to zero, the condition if (--hist_field->ref > 1) always passes since unsigned int wraps. kmemleak report 3: [] __kmalloc_track_caller+0x139/0x2b0 [] kstrdup+0x27/0x50 [<39d70006>] init_var_ref+0x58/0xd0 [<8ca76370>] create_var_ref+0x89/0xe0 [] action_create+0x38f/0xc80 [<7c146821>] event_hist_trigger_func+0x15b5/0x1920 [<07de3f61>] trigger_process_regex+0x7b/0xc0 [] event_trigger_write+0x4d/0xb0 [<19bf1512>] __vfs_write+0x30/0x200 [<64ce4d27>] vfs_write+0x96/0x1b0 [] ksys_write+0x53/0xc0 [<7d4230cd>] __ia32_sys_write+0x15/0x20 [<8eadca00>] do_fast_syscall_32+0x70/0x250 [<235cf985>] entry_SYSENTER_32+0xaf/0x102 hist_fields (system & event_name) are not freed Link: http://lkml.kernel.org/r/20200422061503.GA5151@cosmos Signed-off-by: Vamshi K Sthambamkadi Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_events_hist.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'kernel') diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 5f6834a2bf41..fcab11cc6833 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -3320,6 +3320,9 @@ static void __destroy_hist_field(struct hist_field *hist_field) kfree(hist_field->name); kfree(hist_field->type); + kfree(hist_field->system); + kfree(hist_field->event_name); + kfree(hist_field); } @@ -4382,6 +4385,7 @@ static struct hist_field *create_var(struct hist_trigger_data *hist_data, goto out; } + var->ref = 1; var->flags = HIST_FIELD_FL_VAR; var->var.idx = idx; var->var.hist_data = var->hist_data = hist_data; @@ -5011,6 +5015,9 @@ static void destroy_field_vars(struct hist_trigger_data *hist_data) for (i = 0; i < hist_data->n_field_vars; i++) destroy_field_var(hist_data->field_vars[i]); + + for (i = 0; i < hist_data->n_save_vars; i++) + destroy_field_var(hist_data->save_vars[i]); } static void save_field_var(struct hist_trigger_data *hist_data, -- cgit v1.2.3 From 353da87921a5ec654e7e9024e083f099f1b33c97 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Wed, 22 Apr 2020 21:38:45 -0400 Subject: ftrace: Fix memory leak caused by not freeing entry in unregister_ftrace_direct() kmemleak reported the following: unreferenced object 0xffff90d47127a920 (size 32): comm "modprobe", pid 1766, jiffies 4294792031 (age 162.568s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 22 01 00 00 00 00 ad de ........"....... 00 78 12 a7 ff ff ff ff 00 00 b6 c0 ff ff ff ff .x.............. backtrace: [<00000000bb79e72e>] register_ftrace_direct+0xcb/0x3a0 [<00000000295e4f79>] do_one_initcall+0x72/0x340 [<00000000873ead18>] do_init_module+0x5a/0x220 [<00000000974d9de5>] load_module+0x2235/0x2550 [<0000000059c3d6ce>] __do_sys_finit_module+0xc0/0x120 [<000000005a8611b4>] do_syscall_64+0x60/0x230 [<00000000a0cdc49e>] entry_SYSCALL_64_after_hwframe+0x49/0xb3 The entry used to save the direct descriptor needs to be freed when unregistering. Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/ftrace.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 041694a1eb74..bd030b1b9514 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5165,6 +5165,7 @@ int unregister_ftrace_direct(unsigned long ip, unsigned long addr) list_del_rcu(&direct->next); synchronize_rcu_tasks(); kfree(direct); + kfree(entry); ftrace_direct_func_count--; } } -- cgit v1.2.3 From d013496f99c5608e0f80afd67acb1ba93c4144ea Mon Sep 17 00:00:00 2001 From: Jason Yan Date: Fri, 10 Apr 2020 15:33:12 +0800 Subject: tracing: Convert local functions in tracing_map.c to static Fix the following sparse warning: kernel/trace/tracing_map.c:286:6: warning: symbol 'tracing_map_array_clear' was not declared. Should it be static? kernel/trace/tracing_map.c:297:6: warning: symbol 'tracing_map_array_free' was not declared. Should it be static? kernel/trace/tracing_map.c:319:26: warning: symbol 'tracing_map_array_alloc' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20200410073312.38855-1-yanaijie@huawei.com Reported-by: Hulk Robot Signed-off-by: Jason Yan Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/tracing_map.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c index 9e31bfc818ff..74738c9856f1 100644 --- a/kernel/trace/tracing_map.c +++ b/kernel/trace/tracing_map.c @@ -283,7 +283,7 @@ int tracing_map_add_key_field(struct tracing_map *map, return idx; } -void tracing_map_array_clear(struct tracing_map_array *a) +static void tracing_map_array_clear(struct tracing_map_array *a) { unsigned int i; @@ -294,7 +294,7 @@ void tracing_map_array_clear(struct tracing_map_array *a) memset(a->pages[i], 0, PAGE_SIZE); } -void tracing_map_array_free(struct tracing_map_array *a) +static void tracing_map_array_free(struct tracing_map_array *a) { unsigned int i; @@ -316,7 +316,7 @@ void tracing_map_array_free(struct tracing_map_array *a) kfree(a); } -struct tracing_map_array *tracing_map_array_alloc(unsigned int n_elts, +static struct tracing_map_array *tracing_map_array_alloc(unsigned int n_elts, unsigned int entry_size) { struct tracing_map_array *a; -- cgit v1.2.3