From 0a4d0564f0fc377ad0ba66ce214b9b16324aea4b Mon Sep 17 00:00:00 2001 From: Jérémy Lefaure Date: Sun, 15 Oct 2017 21:22:49 -0400 Subject: tracing: Use ARRAY_SIZE() macro instead of open coding it MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It is useless to re-invent the ARRAY_SIZE macro so let's use it instead of DATA_CNT. Found with Coccinelle with the following semantic patch: @r depends on (org || report)@ type T; T[] E; position p; @@ ( (sizeof(E)@p /sizeof(*E)) | (sizeof(E)@p /sizeof(E[...])) | (sizeof(E)@p /sizeof(T)) ) Link: http://lkml.kernel.org/r/20171016012250.26453-1-jeremy.lefaure@lse.epita.fr Signed-off-by: Jérémy Lefaure [ Removed useless include of kernel.h ] Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_events_filter.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 1bda4ec95e18..5eba1cec945c 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -2140,7 +2140,7 @@ static struct test_filter_data_t { #undef YES #undef NO -#define DATA_CNT (sizeof(test_filter_data)/sizeof(struct test_filter_data_t)) +#define DATA_CNT ARRAY_SIZE(test_filter_data) static int test_pred_visited; -- cgit v1.2.3 From f0a2aa5a2a406d0a57aa9b320ffaa5538672b6c5 Mon Sep 17 00:00:00 2001 From: Howard McLauchlan Date: Tue, 10 Apr 2018 16:10:30 -0700 Subject: tracing/uprobe: Add support for overlayfs uprobes cannot successfully attach to binaries located in a directory mounted with overlayfs. To verify, create directories for mounting overlayfs (upper,lower,work,merge), move some binary into merge/ and use readelf to obtain some known instruction of the binary. I used /bin/true and the entry instruction(0x13b0): $ mount -t overlay overlay -o lowerdir=lower,upperdir=upper,workdir=work merge $ cd /sys/kernel/debug/tracing $ echo 'p:true_entry PATH_TO_MERGE/merge/true:0x13b0' > uprobe_events $ echo 1 > events/uprobes/true_entry/enable This returns 'bash: echo: write error: Input/output error' and dmesg tells us 'event trace: Could not enable event true_entry' This change makes create_trace_uprobe() look for the real inode of a dentry. In the case of normal filesystems, this simplifies to just returning the inode. In the case of overlayfs(and similar fs) we will obtain the underlying dentry and corresponding inode, upon which uprobes can successfully register. Running the example above with the patch applied, we can see that the uprobe is enabled and will output to trace as expected. Link: http://lkml.kernel.org/r/20180410231030.2720-1-hmclauchlan@fb.com Reviewed-by: Josef Bacik Reviewed-by: Masami Hiramatsu Reviewed-by: Srikar Dronamraju Signed-off-by: Howard McLauchlan Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_uprobe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 268029ae1be6..8b86d76c55ee 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -446,7 +446,7 @@ static int create_trace_uprobe(int argc, char **argv) if (ret) goto fail_address_parse; - inode = igrab(d_inode(path.dentry)); + inode = igrab(d_real_inode(path.dentry)); path_put(&path); if (!inode || !S_ISREG(inode->i_mode)) { -- cgit v1.2.3 From 18d45b11d96e6f9b3814960a1394083a3d6b7f74 Mon Sep 17 00:00:00 2001 From: Ravi Bangoria Date: Thu, 15 Mar 2018 13:57:55 +0530 Subject: trace_uprobe: Use %lx to display offset tu->offset is unsigned long, not a pointer, thus %lx should be used to print it, not the %px. Link: http://lkml.kernel.org/r/20180315082756.9050-1-ravi.bangoria@linux.vnet.ibm.com Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu Fixes: 0e4d819d0893 ("trace_uprobe: Display correct offset in uprobe_events") Suggested-by: Kees Cook Signed-off-by: Ravi Bangoria Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_uprobe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 8b86d76c55ee..d7d3c9237f64 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -608,7 +608,7 @@ static int probes_seq_show(struct seq_file *m, void *v) /* Don't print "0x (null)" when offset is 0 */ if (tu->offset) { - seq_printf(m, "0x%px", (void *)tu->offset); + seq_printf(m, "0x%0*lx", (int)(sizeof(void *) * 2), tu->offset); } else { switch (sizeof(void *)) { case 4: -- cgit v1.2.3 From a64b2c01e67eff8b8d0d438507fd0346290697cf Mon Sep 17 00:00:00 2001 From: Ravi Bangoria Date: Thu, 15 Mar 2018 13:57:56 +0530 Subject: trace_uprobe: Simplify probes_seq_show() Simplify probes_seq_show() function. No change in output before and after patch. Link: http://lkml.kernel.org/r/20180315082756.9050-2-ravi.bangoria@linux.vnet.ibm.com Acked-by: Masami Hiramatsu Signed-off-by: Ravi Bangoria Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_uprobe.c | 21 +++------------------ 1 file changed, 3 insertions(+), 18 deletions(-) (limited to 'kernel') diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index d7d3c9237f64..21604754bb79 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -602,24 +602,9 @@ static int probes_seq_show(struct seq_file *m, void *v) char c = is_ret_probe(tu) ? 'r' : 'p'; int i; - seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system, - trace_event_name(&tu->tp.call)); - seq_printf(m, " %s:", tu->filename); - - /* Don't print "0x (null)" when offset is 0 */ - if (tu->offset) { - seq_printf(m, "0x%0*lx", (int)(sizeof(void *) * 2), tu->offset); - } else { - switch (sizeof(void *)) { - case 4: - seq_printf(m, "0x00000000"); - break; - case 8: - default: - seq_printf(m, "0x0000000000000000"); - break; - } - } + seq_printf(m, "%c:%s/%s %s:0x%0*lx", c, tu->tp.call.class->system, + trace_event_name(&tu->tp.call), tu->filename, + (int)(sizeof(void *) * 2), tu->offset); for (i = 0; i < tu->tp.nr_args; i++) seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm); -- cgit v1.2.3 From 0b3dec05dbbce023f4f25aba975b5d253c313ebb Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Wed, 11 Apr 2018 10:59:46 -0400 Subject: tracing: Enforce passing in filter=NULL to create_filter() There's some inconsistency with what to set the output parameter filterp when passing to create_filter(..., struct event_filter **filterp). Whatever filterp points to, should be NULL when calling this function. The create_filter() calls create_filter_start() with a pointer to a local "filter" variable that is set to NULL. The create_filter_start() has a WARN_ON() if the passed in pointer isn't pointing to a value set to NULL. Ideally, create_filter() should pass the filterp variable it received to create_filter_start() and not hide it as with a local variable, this allowed create_filter() to fail, and not update the passed in filter, and the caller of create_filter() then tried to free filter, which was never initialized to anything, causing memory corruption. Link: http://lkml.kernel.org/r/00000000000032a0c30569916870@google.com Fixes: 80765597bc587 ("tracing: Rewrite filter logic to be simpler and faster") Reported-by: syzbot+dadcc936587643d7f568@syzkaller.appspotmail.com Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_events_filter.c | 24 ++++++++++-------------- 1 file changed, 10 insertions(+), 14 deletions(-) (limited to 'kernel') diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 5eba1cec945c..9b4716bb8bb0 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -1704,18 +1704,16 @@ static int create_filter(struct trace_event_call *call, struct event_filter **filterp) { struct filter_parse_error *pe = NULL; - struct event_filter *filter = NULL; int err; - err = create_filter_start(filter_string, set_str, &pe, &filter); + err = create_filter_start(filter_string, set_str, &pe, filterp); if (err) return err; - err = process_preds(call, filter_string, filter, pe); + err = process_preds(call, filter_string, *filterp, pe); if (err && set_str) - append_filter_err(pe, filter); + append_filter_err(pe, *filterp); - *filterp = filter; return err; } @@ -1739,24 +1737,22 @@ static int create_system_filter(struct trace_subsystem_dir *dir, struct trace_array *tr, char *filter_str, struct event_filter **filterp) { - struct event_filter *filter = NULL; struct filter_parse_error *pe = NULL; int err; - err = create_filter_start(filter_str, true, &pe, &filter); + err = create_filter_start(filter_str, true, &pe, filterp); if (!err) { err = process_system_preds(dir, tr, pe, filter_str); if (!err) { /* System filters just show a default message */ - kfree(filter->filter_string); - filter->filter_string = NULL; + kfree((*filterp)->filter_string); + (*filterp)->filter_string = NULL; } else { - append_filter_err(pe, filter); + append_filter_err(pe, *filterp); } } create_filter_finish(pe); - *filterp = filter; return err; } @@ -1764,7 +1760,7 @@ static int create_system_filter(struct trace_subsystem_dir *dir, int apply_event_filter(struct trace_event_file *file, char *filter_string) { struct trace_event_call *call = file->event_call; - struct event_filter *filter; + struct event_filter *filter = NULL; int err; if (!strcmp(strstrip(filter_string), "0")) { @@ -1817,7 +1813,7 @@ int apply_subsystem_event_filter(struct trace_subsystem_dir *dir, { struct event_subsystem *system = dir->subsystem; struct trace_array *tr = dir->tr; - struct event_filter *filter; + struct event_filter *filter = NULL; int err = 0; mutex_lock(&event_mutex); @@ -2024,7 +2020,7 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id, char *filter_str) { int err; - struct event_filter *filter; + struct event_filter *filter = NULL; struct trace_event_call *call; mutex_lock(&event_mutex); -- cgit v1.2.3