user/sven/linux.git/kernel/trace/trace_fprobe.c, branch v6.16.2

Merge tag 'probes-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2025-04-08T19:51:34Z

Pull probes fixes from Masami Hiramatsu: - fprobe: remove fprobe_hlist_node when module unloading When a fprobe target module is removed, the fprobe_hlist_node should be removed from the fprobe's hash table to prevent reusing accidentally if another module is loaded at the same address. - fprobe: lock module while registering fprobe The module containing the function to be probeed is locked using a reference counter until the fprobe registration is complete, which prevents use after free. - fprobe-events: fix possible UAF on modules Basically as same as above, but in the fprobe-events layer we also need to get module reference counter when we find the tracepoint in the module. * tag 'probes-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: fprobe: Cleanup fprobe hash when module unloading tracing: fprobe events: Fix possible UAF on modules tracing: fprobe: Fix to lock module while registering fprobe

tracing: fprobe events: Fix possible UAF on modules

2025-04-02T14:18:58Z

Commit ac91052f0ae5 ("tracing: tprobe-events: Fix leakage of module refcount") moved try_module_get() from __find_tracepoint_module_cb() to find_tracepoint() caller, but that introduced a possible UAF because the module can be unloaded before try_module_get(). In this case, the module object should be freed too. Thus, try_module_get() does not only fail but may access to the freed object. To avoid that, try_module_get() in __find_tracepoint_module_cb() again. Link: https://lore.kernel.org/all/174342990779.781946.9138388479067729366.stgit@devnote2/ Fixes: ac91052f0ae5 ("tracing: tprobe-events: Fix leakage of module refcount") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google)

tracing: probe-events: Log error for exceeding the number of arguments

2025-03-27T12:19:54Z

Add error message when the number of arguments exceeds the limitation. Link: https://lore.kernel.org/all/174055075075.4079315.10916648136898316476.stgit@mhiramat.tok.corp.google.com/ Signed-off-by: Masami Hiramatsu (Google) Reviewed-by: Steven Rostedt (Google)

tracing: tprobe-events: Fix leakage of module refcount

2025-03-14T23:37:47Z

When enabling the tracepoint at loading module, the target module refcount is incremented by find_tracepoint_in_module(). But it is unnecessary because the module is not unloaded while processing module loading callbacks. Moreover, the refcount is not decremented in that function. To be clear the module refcount handling, move the try_module_get() callsite to trace_fprobe_create_internal(), where it is actually required. Link: https://lore.kernel.org/all/174182761071.83274.18334217580449925882.stgit@devnote2/ Fixes: 57a7e6de9e30 ("tracing/fprobe: Support raw tracepoints on future loaded modules") Signed-off-by: Masami Hiramatsu (Google) Cc: stable@vger.kernel.org

tracing: tprobe-events: Fix to clean up tprobe correctly when module unload

2025-03-14T23:37:12Z

When unloading module, the tprobe events are not correctly cleaned up. Thus it becomes `fprobe-event` and never be enabled again even if loading the same module again. For example; # cd /sys/kernel/tracing # modprobe trace_events_sample # echo 't:my_tprobe foo_bar' >> dynamic_events # cat dynamic_events t:tracepoints/my_tprobe foo_bar # rmmod trace_events_sample # cat dynamic_events f:tracepoints/my_tprobe foo_bar As you can see, the second time my_tprobe starts with 'f' instead of 't'. This unregisters the fprobe and tracepoint callback when module is unloaded but marks the fprobe-event is tprobe-event. Link: https://lore.kernel.org/all/174158724946.189309.15826571379395619524.stgit@mhiramat.tok.corp.google.com/ Fixes: 57a7e6de9e30 ("tracing/fprobe: Support raw tracepoints on future loaded modules") Signed-off-by: Masami Hiramatsu (Google)

tracing: fprobe-events: Log error for exceeding the number of entry args

2025-02-27T00:11:51Z

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)

tracing: tprobe-events: Reject invalid tracepoint name

2025-02-27T00:10:58Z

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

tracing: tprobe-events: Fix a memory leak when tprobe with $retval

2025-02-27T00:10:21Z

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

tracing: Adopt __free() and guard() for trace_fprobe.c

2025-01-17T02:27:07Z

Adopt __free() and guard() for trace_fprobe.c to remove gotos. Link: https://lore.kernel.org/173708043449.319651.12242878905778792182.stgit@mhiramat.roam.corp.google.com Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google)

tracing/fprobe: Remove nr_maxactive from fprobe

2024-12-26T15:50:05Z

Remove depercated fprobe::nr_maxactive. This involves fprobe events to rejects the maxactive number. Cc: Alexei Starovoitov Cc: Florent Revest Cc: Martin KaFai Lau Cc: bpf Cc: Alexei Starovoitov Cc: Jiri Olsa Cc: Alan Maguire Cc: Mark Rutland Link: https://lore.kernel.org/173519007257.391279.946804046982289337.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google)