kernel/tools/tracing/rtla/src/actions.c, branch linux-rolling-stable

rtla: Fix NULL pointer dereference in actions_parse

2026-03-04T12:20:13Z

[ Upstream commit a0890f9dbd24b302d327fe7dad9b9c5be0e278aa ] The actions_parse() function uses strtok() to tokenize the trigger string, but does not check if the returned token is NULL before passing it to strcmp(). If the trigger parameter is an empty string or contains only delimiter characters, strtok() returns NULL, causing strcmp() to dereference a NULL pointer and crash the program. This issue can be triggered by malformed user input or edge cases in trigger string parsing. Add a NULL check immediately after the strtok() call to validate that a token was successfully extracted before using it. If no token is found, the function now returns -1 to indicate a parsing error. Signed-off-by: Wander Lairson Costa Link: https://lore.kernel.org/r/20260106133655.249887-13-wander@redhat.com Signed-off-by: Tomas Glozar Signed-off-by: Sasha Levin

Merge tag 'trace-tools-v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2025-10-05T16:38:26Z

Pull tracing tools updates from Steven Rostedt - This is mostly just consolidating code between osnoise/timerlat and top/hist for easier maintenance and less future divergence * tag 'trace-tools-v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tools/rtla: Add remaining support for osnoise actions tools/rtla: Add test engine support for unexpected output tools/rtla: Fix -A option name in test comment tools/rtla: Consolidate code between osnoise/timerlat and hist/top tools/rtla: Create common_apply_config() tools/rtla: Move top/hist params into common struct tools/rtla: Consolidate common parameters into shared structure

rtla/actions: Fix condition for buffer reallocation

2025-09-27T10:01:20Z

The condition to check if the actions buffer needs to be resized was incorrect. The check `self->size >= self->len` would evaluate to true on almost every call to `actions_new()`, causing the buffer to be reallocated unnecessarily each time an action was added. Fix the condition to `self->len >= self.size`, ensuring that the buffer is only resized when it is actually full. Cc: John Kacur Cc: Luis Goncalves Cc: Arnaldo Carvalho de Melo Cc: Chang Yin Cc: Costa Shulyupin Cc: Crystal Wood Cc: Gabriele Monaco Link: https://lore.kernel.org/20250915181101.52513-1-wander@redhat.com Fixes: 6ea082b171e00 ("rtla/timerlat: Add action on threshold feature") Signed-off-by: Wander Lairson Costa Reviewed-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)

rtla: Fix buffer overflow in actions_parse

2025-09-27T09:57:29Z

Currently, tests 3 and 13-22 in tests/timerlat.t fail with error: *** buffer overflow detected ***: terminated timeout: the monitored command dumped core The result of running `sudo make check` is tests/timerlat.t (Wstat: 0 Tests: 22 Failed: 11) Failed tests: 3, 13-22 Files=3, Tests=34, 140 wallclock secs ( 0.07 usr 0.01 sys + 27.63 cusr 27.96 csys = 55.67 CPU) Result: FAIL Fix buffer overflow in actions_parse to avoid this error. After this change, the tests results are tests/hwnoise.t ... ok tests/osnoise.t ... ok tests/timerlat.t .. ok All tests successful. Files=3, Tests=34, 186 wallclock secs ( 0.06 usr 0.01 sys + 41.10 cusr 44.38 csys = 85.55 CPU) Result: PASS Link: https://lore.kernel.org/164ffc2ec8edacaf1295789dad82a07817b6263d.1757034919.git.ipravdin.official@gmail.com Fixes: 6ea082b171e0 ("rtla/timerlat: Add action on threshold feature") Signed-off-by: Ivan Pravdin Reviewed-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)

tools/rtla: Add remaining support for osnoise actions

2025-09-27T08:53:48Z

The basic functionality came with the consolidation; now hook up the command line options, and add documentation and tests. Cc: John Kacur Cc: Costa Shulyupin Link: https://lore.kernel.org/20250907022325.243930-8-crwood@redhat.com Reviewed-by: Tomas Glozar Signed-off-by: Crystal Wood Signed-off-by: Steven Rostedt (Google)

rtla/timerlat: Add continue action

2025-07-25T20:43:57Z

Introduce option to resume tracing after a latency threshold overflow. The option is implemented as an action named "continue". Example: $ rtla timerlat top -q -T 200 -d 1s --on-threshold \ exec,command="echo Threshold" --on-threshold continue Threshold Threshold Threshold Timer Latency ... The feature is supported for both hist and top. After the continue action is executed, processing of the list of actions is stopped and tracing is resumed. Cc: John Kacur Cc: Luis Goncalves Cc: Arnaldo Carvalho de Melo Cc: Chang Yin Cc: Costa Shulyupin Cc: Crystal Wood Cc: Gabriele Monaco Link: https://lore.kernel.org/20250626123405.1496931-5-tglozar@redhat.com Signed-off-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)

rtla/timerlat: Add action on threshold feature

2025-07-25T20:43:56Z

Extend the functionality provided by the -t/--trace option, which triggers saving the contents of a tracefs buffer after tracing is stopped, to support implementing arbitrary actions. A new option, --on-threshold, is added, taking an argument that further specifies the action. Actions added in this patch are: - trace[,file=]: Saves tracefs buffer, optionally taking a filename. - signal,num=,pid=: Sends signal to process. "parent" might be specified instead of number to send signal to parent process. - shell,command=: Execute shell command. Multiple actions may be specified and will be executed in order, including multiple actions of the same type. Trace output requested via -t and -a now adds a trace action to the end of the list. If an action fails, the following actions are not executed. For example, this command: $ rtla timerlat -T 20 --on-threshold trace \ --on-threshold shell,command="grep ipi_send timerlat_trace.txt" \ --on-threshold signal,num=2,pid=parent will send signal 2 (SIGINT) to parent process, but only if saved trace contains the text "ipi_send". This way, the feature can be used for flexible reactions on latency spikes, and allows combining rtla with other tooling like perf. Cc: John Kacur Cc: Luis Goncalves Cc: Arnaldo Carvalho de Melo Cc: Chang Yin Cc: Costa Shulyupin Cc: Crystal Wood Cc: Gabriele Monaco Link: https://lore.kernel.org/20250626123405.1496931-3-tglozar@redhat.com Signed-off-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)