From d5e47505e02666d5b3fe99212e0100791847dc8d Mon Sep 17 00:00:00 2001 From: Miroslav Benes Date: Mon, 31 Aug 2020 14:26:31 +0200 Subject: ftrace: Free the trampoline when ftrace_startup() fails Commit fc0ea795f53c ("ftrace: Add symbols for ftrace trampolines") missed to remove ops from new ftrace_ops_trampoline_list in ftrace_startup() if ftrace_hash_ipmodify_enable() fails there. It may lead to BUG if such ops come from a module which may be removed. Moreover, the trampoline itself is not freed in this case. Fix it by calling ftrace_trampoline_free() during the rollback. Link: https://lkml.kernel.org/r/20200831122631.28057-1-mbenes@suse.cz Fixes: fc0ea795f53c ("ftrace: Add symbols for ftrace trampolines") Fixes: f8b8be8a310a ("ftrace, kprobes: Support IPMODIFY flag to find IP modify conflict") Signed-off-by: Miroslav Benes Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/ftrace.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel/trace') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 275441254bb5..656d7cb5a78c 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2862,6 +2862,8 @@ int ftrace_startup(struct ftrace_ops *ops, int command) __unregister_ftrace_function(ops); ftrace_start_up--; ops->flags &= ~FTRACE_OPS_FL_ENABLED; + if (ops->flags & FTRACE_OPS_FL_DYNAMIC) + ftrace_trampoline_free(ops); return ret; } -- cgit v1.2.3-71-gd317 From 478ece9573f04aed834e05e0bbf034320d240f9f Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Tue, 1 Sep 2020 12:16:17 +0300 Subject: ftrace: Fix missing synchronize_rcu() removing trampoline from kallsyms Add synchronize_rcu() after list_del_rcu() in ftrace_remove_trampoline_from_kallsyms() to protect readers of ftrace_ops_trampoline_list (in ftrace_get_trampoline_kallsym) which is used when kallsyms is read. Link: https://lkml.kernel.org/r/20200901091617.31837-1-adrian.hunter@intel.com Fixes: fc0ea795f53c8d ("ftrace: Add symbols for ftrace trampolines") Signed-off-by: Adrian Hunter Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/ftrace.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel/trace') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 656d7cb5a78c..e9f893388245 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2782,6 +2782,7 @@ static void ftrace_remove_trampoline_from_kallsyms(struct ftrace_ops *ops) { lockdep_assert_held(&ftrace_lock); list_del_rcu(&ops->list); + synchronize_rcu(); } /* -- cgit v1.2.3-71-gd317 From 795d6379a47bcbb88bd95a69920e4acc52849f88 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Fri, 4 Sep 2020 10:23:31 +0200 Subject: tracing: Make the space reserved for the pid wider For 64bit CONFIG_BASE_SMALL=0 systems PID_MAX_LIMIT is set by default to 4194304. During boot the kernel sets a new value based on number of CPUs but no lower than 32768. It is 1024 per CPU so with 128 CPUs the default becomes 131072 which needs six digits. This value can be increased during run time but must not exceed the initial upper limit. Systemd sometime after v241 sets it to the upper limit during boot. The result is that when the pid exceeds five digits, the trace output is a little hard to read because it is no longer properly padded (same like on big iron with 98+ CPUs). Increase the pid padding to seven digits. Link: https://lkml.kernel.org/r/20200904082331.dcdkrr3bkn3e4qlg@linutronix.de Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 38 +++++++++++++++++++------------------- kernel/trace/trace_output.c | 12 ++++++------ 2 files changed, 25 insertions(+), 25 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f40d850ebabc..2a7c26345e83 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3782,14 +3782,14 @@ unsigned long trace_total_entries(struct trace_array *tr) static void print_lat_help_header(struct seq_file *m) { - seq_puts(m, "# _------=> CPU# \n" - "# / _-----=> irqs-off \n" - "# | / _----=> need-resched \n" - "# || / _---=> hardirq/softirq \n" - "# ||| / _--=> preempt-depth \n" - "# |||| / delay \n" - "# cmd pid ||||| time | caller \n" - "# \\ / ||||| \\ | / \n"); + seq_puts(m, "# _------=> CPU# \n" + "# / _-----=> irqs-off \n" + "# | / _----=> need-resched \n" + "# || / _---=> hardirq/softirq \n" + "# ||| / _--=> preempt-depth \n" + "# |||| / delay \n" + "# cmd pid ||||| time | caller \n" + "# \\ / ||||| \\ | / \n"); } static void print_event_info(struct array_buffer *buf, struct seq_file *m) @@ -3810,26 +3810,26 @@ static void print_func_help_header(struct array_buffer *buf, struct seq_file *m, print_event_info(buf, m); - seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? "TGID " : ""); - seq_printf(m, "# | | %s | | |\n", tgid ? " | " : ""); + seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? " TGID " : ""); + seq_printf(m, "# | | %s | | |\n", tgid ? " | " : ""); } static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file *m, unsigned int flags) { bool tgid = flags & TRACE_ITER_RECORD_TGID; - const char *space = " "; - int prec = tgid ? 10 : 2; + const char *space = " "; + int prec = tgid ? 12 : 2; print_event_info(buf, m); - seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space); - seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space); - seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space); - seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space); - seq_printf(m, "# %.*s||| / delay\n", prec, space); - seq_printf(m, "# TASK-PID %.*sCPU# |||| TIMESTAMP FUNCTION\n", prec, " TGID "); - seq_printf(m, "# | | %.*s | |||| | |\n", prec, " | "); + seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space); + seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space); + seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space); + seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space); + seq_printf(m, "# %.*s||| / delay\n", prec, space); + seq_printf(m, "# TASK-PID %.*s CPU# |||| TIMESTAMP FUNCTION\n", prec, " TGID "); + seq_printf(m, "# | | %.*s | |||| | |\n", prec, " | "); } void diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 4d1893564912..000e9dc224c6 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -497,7 +497,7 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) trace_find_cmdline(entry->pid, comm); - trace_seq_printf(s, "%8.8s-%-5d %3d", + trace_seq_printf(s, "%8.8s-%-7d %3d", comm, entry->pid, cpu); return trace_print_lat_fmt(s, entry); @@ -588,15 +588,15 @@ int trace_print_context(struct trace_iterator *iter) trace_find_cmdline(entry->pid, comm); - trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid); + trace_seq_printf(s, "%16s-%-7d ", comm, entry->pid); if (tr->trace_flags & TRACE_ITER_RECORD_TGID) { unsigned int tgid = trace_find_tgid(entry->pid); if (!tgid) - trace_seq_printf(s, "(-----) "); + trace_seq_printf(s, "(-------) "); else - trace_seq_printf(s, "(%5d) ", tgid); + trace_seq_printf(s, "(%7d) ", tgid); } trace_seq_printf(s, "[%03d] ", iter->cpu); @@ -636,7 +636,7 @@ int trace_print_lat_context(struct trace_iterator *iter) trace_find_cmdline(entry->pid, comm); trace_seq_printf( - s, "%16s %5d %3d %d %08x %08lx ", + s, "%16s %7d %3d %d %08x %08lx ", comm, entry->pid, iter->cpu, entry->flags, entry->preempt_count, iter->idx); } else { @@ -917,7 +917,7 @@ static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter, S = task_index_to_char(field->prev_state); trace_find_cmdline(field->next_pid, comm); trace_seq_printf(&iter->seq, - " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n", + " %7d:%3d:%c %s [%03d] %7d:%3d:%c %s\n", field->prev_pid, field->prev_prio, S, delim, -- cgit v1.2.3-71-gd317 From 54fa9ba564b717fc2cf689427e195c360315999d Mon Sep 17 00:00:00 2001 From: Tobias Klauser Date: Mon, 7 Sep 2020 11:32:07 +0200 Subject: ftrace: Let ftrace_enable_sysctl take a kernel pointer buffer Commit 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") changed ctl_table.proc_handler to take a kernel pointer. Adjust the signature of ftrace_enable_sysctl to match ctl_table.proc_handler which fixes the following sparse warning: kernel/trace/ftrace.c:7544:43: warning: incorrect type in argument 3 (different address spaces) kernel/trace/ftrace.c:7544:43: expected void * kernel/trace/ftrace.c:7544:43: got void [noderef] __user *buffer Link: https://lkml.kernel.org/r/20200907093207.13540-1-tklauser@distanz.ch Fixes: 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") Cc: Andrew Morton Cc: Ingo Molnar Cc: Christoph Hellwig Cc: Al Viro Signed-off-by: Tobias Klauser Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 3 +-- kernel/trace/ftrace.c | 3 +-- 2 files changed, 2 insertions(+), 4 deletions(-) (limited to 'kernel/trace') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index ce2c06f72e86..e5c2d5cc6e6a 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -85,8 +85,7 @@ static inline int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *val extern int ftrace_enabled; extern int ftrace_enable_sysctl(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos); + void *buffer, size_t *lenp, loff_t *ppos); struct ftrace_ops; diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index e9f893388245..603255f5f085 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -7534,8 +7534,7 @@ static bool is_permanent_ops_registered(void) int ftrace_enable_sysctl(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos) + void *buffer, size_t *lenp, loff_t *ppos) { int ret = -ENODEV; -- cgit v1.2.3-71-gd317 From 46bbe5c671e06f070428b9be142cc4ee5cedebac Mon Sep 17 00:00:00 2001 From: Tom Rix Date: Mon, 7 Sep 2020 06:58:45 -0700 Subject: tracing: fix double free clang static analyzer reports this problem trace_events_hist.c:3824:3: warning: Attempt to free released memory kfree(hist_data->attrs->var_defs.name[i]); In parse_var_defs() if there is a problem allocating var_defs.expr, the earlier var_defs.name is freed. This free is duplicated by free_var_defs() which frees the rest of the list. Because free_var_defs() has to run anyway, remove the second free fom parse_var_defs(). Link: https://lkml.kernel.org/r/20200907135845.15804-1-trix@redhat.com Cc: stable@vger.kernel.org Fixes: 30350d65ac56 ("tracing: Add variable support to hist triggers") Reviewed-by: Tom Zanussi Signed-off-by: Tom Rix Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_events_hist.c | 1 - 1 file changed, 1 deletion(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 0b933546142e..1b2ef6490229 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -3865,7 +3865,6 @@ static int parse_var_defs(struct hist_trigger_data *hist_data) s = kstrdup(field_str, GFP_KERNEL); if (!s) { - kfree(hist_data->attrs->var_defs.name[n_vars]); ret = -ENOMEM; goto free; } -- cgit v1.2.3-71-gd317