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11 daystreewide: refresh kmalloc_obj() conversionsKees Cook1-1/+1
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-08-20Merge tag 'probes-v7.3' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: "BTF typecasting and variable fetch enhancements: - Typecast support across probe events: Extended BTF typecasting syntax (e.g., (STRUCT)PARAM->MEMBER) to kprobes, uprobes, and fprobes on function entry and return - Nested typecasts: Added support for chaining and nesting typecasts up to 3 levels, including casting registers and stack variables - Field specifier option: Added (STRUCT,FIELD) syntax to emulate container_of(), allowing retrieval of parent structures from member pointers - $current variable support: Introduced $current special variable to access the running task_struct via BTF dereferencing - Per-CPU variable access: Added this_cpu_read() and this_cpu_ptr() fetcharg methods to trace CPU-local data safely - Fetcharg bytecode dumper: Added CONFIG_PROBE_EVENTS_DUMP_FETCHARG to dump the compiled fetcharg bytecode instructions as comments in dynamic_events - Extended symbol name handling: Removed the MAX_COMMON_HEAD_LEN limit and extended MAX_ARGSTR_LEN to 256 bytes, enabling probing of long symbols, mangled Rust symbols and complex BTF expressions - eprobe variable syntax: Allowed eprobes to reference event fields directly without requiring a '$' prefix - Cleanup unused parameters, redundant codes, duplicate macros and pointer arithmetic - Use a ternary operator for simplifying fetch_type_from_btf_type() Expanded boot time dynamic probe support: - Add boot-time tracing configuration support for event probes (eprobes), function probes (fprobes), and tracepoint probes (tprobes) - Allow comment lines ('#') in dynamic_events file Optimization, robustness, and cleanups: - Simplify fprobe_remove_ips() by reusing graph and ftrace helpers - Remove __packed attribute from struct __fprobe_header to avoid unaligned memory access penalties on RISC architectures - Remove redundant memset() calls in perf event probe handlers - Replace legacy __ASSEMBLY__ with __ASSEMBLER__ in header files Selftests & refactoring: - Refactor parse_probe_arg() and parse_probe_vars(), and eliminate recursion in probe argument parsing to protect kernel stack depth - Add selftests for BTF typecasts and module probing without module prefixes - Force LC_ALL=C in ftracetest to prevent test failures on localized systems - Refactor btf_type_skip_modifiers() to remove ignored id parameter - Sort ERRORS list in trace_probe.h alphabetically - Fix typo in fprobe docs, and trace_fprobe function name - Rename FETCH_OP_DATA to FETCH_OP_IMMSTR - Make file offset error message probe-agnostic" * tag 'probes-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (37 commits) fprobe: Simplify fprobe_remove_ips() by reusing existing helpers tracing/boot: Add support for eprobe, fprobe, and tprobe events selftests/ftrace: Force C locale in ftracetest tracing/probes: Treating longer symbol name on event comparation docs: trace: fprobe: fix 'thos' spelling tracing/probes: Fix extra whitespace in trace_probe_kernel.h tracing/kprobe: Remove redundant memset in kprobe_perf_func() tracing/fprobe: Remove redundant memset in fentry_perf_func() tracing/fprobe: Remove redundant snprintf in trace_fprobe_match_command_head() tracing/probes: Simplify BTF_KIND_PTR case in fetch_type_from_btf_type() tracing/probes: Cleanup pointer arithmetic in store_trace_entry_data() tracing/probes: Remove unused parameter from parse_probe_var_retval() tracing/probes: Remove redundant bounds check in trace_probe_compare_arg_type() tracing/probes: Remove redundant boolean conversion in trace_probe_has_single_file() tracing/probes: Remove duplicate MAX_ARRAY_LEN macro definition selftests/ftrace: Add test case for a symbol in a module without module name tracing/probes: Eliminate recursion in parse_probe_arg() tracing/probes: Extend max length of argument string tracing/probes: Sort ERRORS list in trace_probe.h alphabetically tracing/probes: Refactor parse_probe_arg() ...
2026-07-21tracing/eprobe: Fix exact system name matching in eprobe_dyn_event_match()Masami Hiramatsu (Google)1-1/+2
eprobe_dyn_event_match() checks if the target event system in argv[0] matches ep->event_system using strncmp(ep->event_system, argv[0], len). However, if ep->event_system is longer than len (e.g. "eprobes" vs "ep/event"), strncmp() still returns 0 because the first len characters match. Check that ep->event_system[len] is '\0' to ensure exact system name matching. Link: https://lore.kernel.org/all/178454235856.290363.14872590900774231133.stgit@devnote2/ Fixes: 7d5fda1c841f ("tracing: Fix event probe removal from dynamic events") Cc: stable@vger.kernel.org Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-02tracing/probes: Support dumping fetcharg program for debugging dynamic eventsMasami Hiramatsu (Google)1-0/+2
For debugging probe events, it is helpful to verify the compiled fetch instructions for each probe argument. This introduces a new kernel config CONFIG_PROBE_EVENTS_DUMP_FETCHARG to decode the instruction sequence of each argument and display it under a commented line starting with '#' immediately following the dynamic event definition (such as in dynamic_events, kprobe_events, uprobe_events, etc.). For example: /sys/kernel/tracing # cat dynamic_events p:kprobes/p_vfs_read_0 vfs_read arg1=+0(file):ustring arg2=%ax:x16 # arg1: ARG(0) -> ST_USTRING(offset=0,size=4) -> END # arg2: REG(80) -> ST_RAW(size=2) -> END Link: https://lore.kernel.org/all/178271359508.1176915.11895926894608440183.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-06-30tracing: eprobe: read the complete FILTER_PTR_STRING pointerMartin Kaiser1-1/+1
For a char * element in an event, the FILTER_PTR_STRING filter type is used. When the event occurs, a pointer is stored in the ringbuffer. If an eprobe references such a char * element of a "base event", the stored pointer is truncated when it's read from the ringbuffer. $ cd /sys/kernel/tracing $ echo 'e rcu.rcu_utilization $s:x64 $s:string' > dynamic_events $ echo 1 > tracing_on $ echo 1 > events/eprobes/enable $ sleep 1 $ echo 0 > events/eprobes/enable $ cat trace <idle>-0 ...: (rcu.rcu_utilization) arg1=0x4f arg2=(fault) <idle>-0 ...: (rcu.rcu_utilization) arg1=0x2 arg2=(fault) The problem is in get_event_field val = (unsigned long)(*(char *)addr); addr points to the position in the ringbuffer where the pointer was stored. The assignment reads only the lowest byte of the pointer. Fix the cast to read the whole pointer. The output of the test above is now <idle>-0 ... arg1=0xffffffff81c7d3f3 arg2="Start scheduler-tick" <idle>-0 ... arg1=0xffffffff81c57340 arg2="End scheduler-tick" Link: https://lore.kernel.org/all/20260620145339.3234726-1-martin@kaiser.cx/ Fixes: f04dec93466a ("tracing/eprobes: Fix reading of string fields") Signed-off-by: Martin Kaiser <martin@kaiser.cx> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-02-21Convert 'alloc_flex' family to use the new default GFP_KERNEL argumentLinus Torvalds1-1/+1
This is the exact same thing as the 'alloc_obj()' version, only much smaller because there are a lot fewer users of the *alloc_flex() interface. As with alloc_obj() version, this was done entirely with mindless brute force, using the same script, except using 'flex' in the pattern rather than 'objs*'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds1-2/+2
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook1-3/+3
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2025-12-05Merge tag 'probes-v6.19' of ↵Linus Torvalds1-64/+44
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: "fprobe performance enhancement using rhltable: - use rhltable for fprobe_ip_table. The fprobe IP table has been converted to use an rhltable for improved performance when dealing with a large number of probed functions - Fix a suspicious RCU usage warning of the above change in the fprobe entry handler - Remove an unused local variable of the above change - Fix to initialize fprobe_ip_table in core_initcall() Performance optimization of fprobe by ftrace: - Use ftrace instead of fgraph for entry only probes. This avoids the unneeded overhead of fgraph stack setup - Also update fprobe selftest for entry-only probe - fprobe: Use ftrace only if CONFIG_DYNAMIC_FTRACE_WITH_ARGS or WITH_REGS is defined Cleanup probe event subsystems: - Allocate traceprobe_parse_context per probe instead of each probe argument parsing. This reduce memory allocation/free of temporary working memory - Cleanup code using __free() - Replace strcpy() with memcpy() in __trace_probe_log_err()" * tag 'probes-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: fprobe: use ftrace if CONFIG_DYNAMIC_FTRACE_WITH_ARGS lib/test_fprobe: add testcase for mixed fprobe tracing: fprobe: optimization for entry only case tracing: fprobe: Fix to init fprobe_ip_table earlier tracing: fprobe: Remove unused local variable tracing: probes: Replace strcpy() with memcpy() in __trace_probe_log_err() tracing: fprobe: fix suspicious rcu usage in fprobe_entry tracing: uprobe: eprobes: Allocate traceprobe_parse_context per probe tracing: uprobes: Cleanup __trace_uprobe_create() with __free() tracing: eprobe: Cleanup eprobe event using __free() tracing: probes: Use __free() for trace_probe_log tracing: fprobe: use rhltable for fprobe_ip_table
2025-11-26tracing: Merge struct event_trigger_ops into struct event_commandSteven Rostedt1-9/+4
Now that there's pretty much a one to one mapping between the struct event_trigger_ops and struct event_command, there's no reason to have two different structures. Merge the function pointers of event_trigger_ops into event_command. There's one exception in trace_events_hist.c for the event_hist_trigger_named_ops. This has special logic for the init and free function pointers for "named histograms". In this case, allocate the cmd_ops of the event_trigger_data and set it to the proper init and free functions, which are used to initialize and free the event_trigger_data respectively. Have the free function and the init function (on failure) free the cmd_ops of the data element. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251125200932.446322765@kernel.org Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Remove get_trigger_ops() and add count_func() from trigger opsSteven Rostedt1-7/+1
The struct event_command has a callback function called get_trigger_ops(). This callback returns the "trigger_ops" to use for the trigger. These ops define the trigger function, how to init the trigger, how to print the trigger and how to free it. The only reason there's a callback function to get these ops is because some triggers have two types of operations. One is an "always on" operation, and the other is a "count down" operation. If a user passes in a parameter to say how many times the trigger should execute. For example: echo stacktrace:5 > events/kmem/kmem_cache_alloc/trigger It will trigger the stacktrace for the first 5 times the kmem_cache_alloc event is hit. Instead of having two different trigger_ops since the only difference between them is the tigger itself (the print, init and free functions are all the same), just use a single ops that the event_command points to and add a function field to the trigger_ops to have a count_func. When a trigger is added to an event, if there's a count attached to it and the trigger ops has the count_func field, the data allocated to represent this trigger will have a new flag set called COUNT. Then when the trigger executes, it will check if the COUNT data flag is set, and if so, it will call the ops count_func(). If that returns false, it returns without executing the trigger. This removes the need for duplicate event_trigger_ops structures. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251125200932.274566147@kernel.org Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-01tracing: uprobe: eprobes: Allocate traceprobe_parse_context per probeMasami Hiramatsu (Google)1-20/+12
Since traceprobe_parse_context is reusable among a probe arguments, it is more efficient to allocate it outside of the loop for parsing probe argument as kprobe and fprobe events do. Link: https://lore.kernel.org/all/175509541393.193596.16330324746701582114.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-11-01tracing: eprobe: Cleanup eprobe event using __free()Masami Hiramatsu (Google)1-41/+30
Use __free(trace_event_probe_cleanup) to remove unneeded gotos and cleanup the last part of trace_eprobe_parse_filter(). Link: https://lore.kernel.org/all/175509539571.193596.4674012182718751429.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-11-01tracing: probes: Use __free() for trace_probe_logMasami Hiramatsu (Google)1-3/+2
Use __free() for trace_probe_log_clear() to cleanup error log interface. Link: https://lore.kernel.org/all/175509538609.193596.16646724647358218778.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-07-24tracing: Have eprobes handle arraysSteven Rostedt1-4/+9
eprobes are dynamic events that can read other events using their fields to create new events. Currently it doesn't work with arrays. When the new event field is attached to the old event field, it looks at the size of the field to determine what type of field the new field should be. For 1 byte fields it's a char, for 2 bytes, it's a short and for 4 bytes it's an integer. For all other sizes it just defaults to "long". This also reads the contents of the field for such cases. For arrays that are bigger than the size of long, return the value of the address of the content itself. This will allow eprobes to read other values in the array of the old event. This is useful when raw_syscalls is enabled but the syscall events are not. The syscall events are created from the raw_syscalls as they have an array of "args" that holds the 6 long words passed to the syscall entry point. To read the value of "filename" from sys_openat, the eprobe could attach to the raw_syscall and read the second value. It can then even be passed to a synthetic event and converted back to another eprobe to get the value of "filename" after it has been read by the kernel during the system call: [ Create an eprobe called "sys" and attach it to sys_enter. Read the id of the system call and the second argument ] # echo 'e:sys raw_syscalls.sys_enter nr=$id:u32 arg2=+8($args):u64' >> /sys/kernel/tracing/dynamic_events [ Create a synthetic event "path" that will hold the address of the sys_openat filename. This is on a 64bit machine, so make it 64 bits ] # echo 's:path u64 file;' >> /sys/kernel/tracing/dynamic_events [ Add a histogram to the eprobe/sys which tiggers if the "nr" field is 257 (sys_openat), and save the filename in the "file" variable. ] # echo 'hist:keys=common_pid:file=arg2 if nr == 257' > /sys/kernel/tracing/events/eprobes/sys/trigger [ Attach a histogram to sys_exit event that triggers the "path" synthetic event and records the "filename" that was passed from the sys eprobe. ] # echo 'hist:keys=common_pid:f=$file:onmatch(eprobes.sys).trace(path,$f)' >> /sys/kernel/tracing/events/raw_syscalls/sys_exit/trigger [ Create another eprobe that dereferences the "file" field as a user space string and displays it. ] # echo 'e:open synthetic.path file=+0($file):ustring' >> /sys/kernel/tracing/dynamic_events # echo 1 > /sys/kernel/tracing/events/eprobes/open/enable # cat trace_pipe cat-1142 [003] ...5. 799.521912: open: (synthetic.path) file="/etc/ld.so.cache" cat-1142 [003] ...5. 799.521934: open: (synthetic.path) file="/etc/ld.so.cache" cat-1142 [003] ...5. 799.522065: open: (synthetic.path) file="/etc/ld.so.cache" cat-1142 [003] ...5. 799.522080: open: (synthetic.path) file="/etc/ld.so.cache" cat-1142 [003] ...5. 799.522296: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libc.so.6" cat-1142 [003] ...5. 799.522319: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libc.so.6" less-1143 [005] ...5. 799.522327: open: (synthetic.path) file="/etc/ld.so.cache" cat-1142 [003] ...5. 799.522333: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libc.so.6" cat-1142 [003] ...5. 799.522348: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libc.so.6" less-1143 [005] ...5. 799.522349: open: (synthetic.path) file="/etc/ld.so.cache" cat-1142 [003] ...5. 799.522363: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libc.so.6" less-1143 [005] ...5. 799.522477: open: (synthetic.path) file="/etc/ld.so.cache" cat-1142 [003] ...5. 799.522489: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libc.so.6" less-1143 [005] ...5. 799.522492: open: (synthetic.path) file="/etc/ld.so.cache" less-1143 [005] ...5. 799.522720: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libtinfo.so.6" less-1143 [005] ...5. 799.522744: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libtinfo.so.6" less-1143 [005] ...5. 799.522759: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libtinfo.so.6" cat-1142 [003] ...5. 799.522850: open: (synthetic.path) file="/lib/x86_64-linux-gnu/libc.so.6" Link: https://lore.kernel.org/all/20250723124202.4f7475be@batman.local.home/ Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-07-24tracing: eprobe-event: Allocate string buffers from heapMasami Hiramatsu (Google)1-4/+18
Allocate temporary string buffers for parsing eprobe-events from heap instead of stack. Link: https://lore.kernel.org/all/175323428599.57270.988038042425748956.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-24tracing: probe: Allocate traceprobe_parse_context from heapMasami Hiramatsu (Google)1-6/+8
Instead of allocating traceprobe_parse_context on stack, allocate it dynamically from heap (slab). This change is likely intended to prevent potential stack overflow issues, which can be a concern in the kernel environment where stack space is limited. Link: https://lore.kernel.org/all/175323425650.57270.280750740753792504.stgit@devnote2/ Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202506240416.nZIhDXoO-lkp@intel.com/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-24tracing: probes: Sort #include alphabeticallyMasami Hiramatsu (Google)1-2/+2
Sort the #include directives in trace_probe* files alphabetically for easier maintenance and avoid double includes. This also groups headers as linux-generic, asm-generic, and local headers. Link: https://lore.kernel.org/all/175323424678.57270.11975372127870059007.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-05-10tracing: add missing trace_probe_log_clear for eprobesPaul Cacheux1-0/+3
Make sure trace_probe_log_clear is called in the tracing eprobe code path, matching the trace_probe_log_init call. Link: https://lore.kernel.org/all/20250504-fix-trace-probe-log-race-v3-1-9e99fec7eddc@gmail.com/ Signed-off-by: Paul Cacheux <paulcacheux@gmail.com> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-03-27Merge tag 'probes-v6.15' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: - probe-events: Add comments about entry data storing code to clarify where and how the entry data is stored for function return events. - probe-events: Log error for exceeding the number of arguments to help user to identify error reason via tracefs/error_log file. - Improve the ftracetest selftests: - Expand the tprobe event test to check if it can correctly find the wrong format tracepoint name. - Add new syntax error test to check whether error_log correctly indicates a wrong character in the tracepoint name. - Add a new dynamic events argument limitation test case which checks max number of probe arguments. * tag 'probes-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: probe-events: Add comments about entry data storing code selftests/ftrace: Add dynamic events argument limitation test case selftests/ftrace: Add new syntax error test selftests/ftrace: Expand the tprobe event test to check wrong format tracing: probe-events: Log error for exceeding the number of arguments
2025-03-27tracing: probe-events: Log error for exceeding the number of argumentsMasami Hiramatsu (Google)1-0/+2
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) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-03-20tracing: Constify struct event_trigger_opsChristophe JAILLET1-3/+3
'event_trigger_ops mwifiex_if_ops' are not modified in these drivers. Constifying these structures moves some data to a read-only section, so increase overall security, especially when the structure holds some function pointers. On a x86_64, with allmodconfig, as an example: Before: ====== text data bss dec hex filename 31368 9024 6200 46592 b600 kernel/trace/trace_events_trigger.o After: ===== text data bss dec hex filename 31752 8608 6200 46560 b5e0 kernel/trace/trace_events_trigger.o Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/66e8f990e649678e4be37d4d1a19158ca0dea2f4.1741521295.git.christophe.jaillet@wanadoo.fr Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-01-10tracing/eprobe: Adopt guard() and scoped_guard()Masami Hiramatsu (Google)1-19/+17
Use guard() or scoped_guard() in eprobe events for critical sections rather than discrete lock/unlock pairs. Link: https://lore.kernel.org/all/173289890996.73724.17421347964110362029.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-12-08tracing/eprobe: Fix to release eprobe when failed to add dyn_eventMasami Hiramatsu (Google)1-0/+5
Fix eprobe event to unregister event call and release eprobe when it fails to add dynamic event correctly. Link: https://lore.kernel.org/all/173289886698.73724.1959899350183686006.stgit@devnote2/ Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-10-23tracing/probes: Fix MAX_TRACE_ARGS limit handlingMikel Rychliski1-1/+6
When creating a trace_probe we would set nr_args prior to truncating the arguments to MAX_TRACE_ARGS. However, we would only initialize arguments up to the limit. This caused invalid memory access when attempting to set up probes with more than 128 fetchargs. BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 UID: 0 PID: 1769 Comm: cat Not tainted 6.11.0-rc7+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014 RIP: 0010:__set_print_fmt+0x134/0x330 Resolve the issue by applying the MAX_TRACE_ARGS limit earlier. Return an error when there are too many arguments instead of silently truncating. Link: https://lore.kernel.org/all/20240930202656.292869-1-mikel@mikelr.com/ Fixes: 035ba76014c0 ("tracing/probes: cleanup: Set trace_probe::nr_args at trace_probe_init") Signed-off-by: Mikel Rychliski <mikel@mikelr.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-03-07tracing/probes: Support $argN in return probe (kprobe and fprobe)Masami Hiramatsu (Google)1-3/+3
Support accessing $argN in the return probe events. This will help users to record entry data in function return (exit) event for simplfing the function entry/exit information in one event, and record the result values (e.g. allocated object/initialized object) at function exit. For example, if we have a function `int init_foo(struct foo *obj, int param)` sometimes we want to check how `obj` is initialized. In such case, we can define a new return event like below; # echo 'r init_foo retval=$retval param=$arg2 field1=+0($arg1)' >> kprobe_events Thus it records the function parameter `param` and its result `obj->field1` (the dereference will be done in the function exit timing) value at once. This also support fprobe, BTF args and'$arg*'. So if CONFIG_DEBUG_INFO_BTF is enabled, we can trace both function parameters and the return value by following command. # echo 'f target_function%return $arg* $retval' >> dynamic_events Link: https://lore.kernel.org/all/170952365552.229804.224112990211602895.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-03-07tracing/probes: cleanup: Set trace_probe::nr_args at trace_probe_initMasami Hiramatsu (Google)1-1/+1
Instead of incrementing the trace_probe::nr_args, init it at trace_probe_init(). Without this change, there is no way to get the number of trace_probe arguments while parsing it. This is a cleanup, so the behavior is not changed. Link: https://lore.kernel.org/all/170952363585.229804.13060759900346411951.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-10-10tracing/eprobe: drop unneeded breaksJulia Lawall1-4/+1
Drop break after return. Link: https://lore.kernel.org/all/20230928104334.41215-1-Julia.Lawall@inria.fr/ Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-08-23tracing/probes: Support BTF argument on module functionsMasami Hiramatsu (Google)1-3/+1
Since the btf returned from bpf_get_btf_vmlinux() only covers functions in the vmlinux, BTF argument is not available on the functions in the modules. Use bpf_find_btf_id() instead of bpf_get_btf_vmlinux()+btf_find_name_kind() so that BTF argument can find the correct struct btf and btf_type in it. With this fix, fprobe events can use `$arg*` on module functions as below # grep nf_log_ip_packet /proc/kallsyms ffffffffa0005c00 t nf_log_ip_packet [nf_log_syslog] ffffffffa0005bf0 t __pfx_nf_log_ip_packet [nf_log_syslog] # echo 'f nf_log_ip_packet $arg*' > dynamic_events # cat dynamic_events f:fprobes/nf_log_ip_packet__entry nf_log_ip_packet net=net pf=pf hooknum=hooknum skb=skb in=in out=out loginfo=loginfo prefix=prefix To support the module's btf which is removable, the struct btf needs to be ref-counted. So this also records the btf in the traceprobe_parse_context and returns the refcount when the parse has done. Link: https://lore.kernel.org/all/169272154223.160970.3507930084247934031.stgit@devnote2/ Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-08-23tracing/eprobe: Iterate trace_eprobe directlyChuang Wang1-9/+9
Refer to the description in [1], we can skip "container_of()" following "list_for_each_entry()" by using "list_for_each_entry()" with "struct trace_eprobe" and "tp.list". Also, this patch defines "for_each_trace_eprobe_tp" to simplify the code of the same logic. [1] https://lore.kernel.org/all/CAHk-=wjakjw6-rDzDDBsuMoDCqd+9ogifR_EE1F0K-jYek1CdA@mail.gmail.com/ Link: https://lore.kernel.org/all/20230822022433.262478-1-nashuiliang@gmail.com/ Signed-off-by: Chuang Wang <nashuiliang@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-12Merge tag 'probes-fixes-v6.5-rc1' of ↵Linus Torvalds1-2/+16
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes fixes from Masami Hiramatsu: - Fix fprobe's rethook release issues: - Release rethook after ftrace_ops is unregistered so that the rethook is not accessed after free. - Stop rethook before ftrace_ops is unregistered so that the rethook is NOT used after exiting unregister_fprobe() - Fix eprobe cleanup logic. If it attaches to multiple events and failes to enable one of them, rollback all enabled events correctly. - Fix fprobe to unlock ftrace recursion lock correctly when it missed by another running kprobe. - Cleanup kprobe to remove unnecessary NULL. - Cleanup kprobe to remove unnecessary 0 initializations. * tag 'probes-fixes-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: fprobe: Ensure running fprobe_exit_handler() finished before calling rethook_free() kernel: kprobes: Remove unnecessary ‘0’ values kprobes: Remove unnecessary ‘NULL’ values from correct_ret_addr fprobe: add unlock to match a succeeded ftrace_test_recursion_trylock kernel/trace: Fix cleanup logic of enable_trace_eprobe fprobe: Release rethook after the ftrace_ops is unregistered
2023-07-11kernel/trace: Fix cleanup logic of enable_trace_eprobeTzvetomir Stoyanov (VMware)1-2/+16
The enable_trace_eprobe() function enables all event probes, attached to given trace probe. If an error occurs in enabling one of the event probes, all others should be roll backed. There is a bug in that roll back logic - instead of all event probes, only the failed one is disabled. Link: https://lore.kernel.org/all/20230703042853.1427493-1-tz.stoyanov@gmail.com/ Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events") Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-06tracing/probes: Move event parameter fetching code to common parserMasami Hiramatsu (Google)1-39/+5
Move trace event parameter fetching code to common parser in trace_probe.c. This simplifies eprobe's trace-event variable fetching code by introducing a parse context data structure. Link: https://lore.kernel.org/all/168507472950.913472.2812253181558471278.stgit@mhiramat.roam.corp.google.com/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-06tracing/probes: Add tracepoint support on fprobe_eventsMasami Hiramatsu (Google)1-1/+1
Allow fprobe_events to trace raw tracepoints so that user can trace tracepoints which don't have traceevent wrappers. This new event is always available if the fprobe_events is enabled (thus no kconfig), because the fprobe_events depends on the trace-event and traceporint. e.g. # echo 't sched_overutilized_tp' >> dynamic_events # echo 't 9p_client_req' >> dynamic_events # cat dynamic_events t:tracepoints/sched_overutilized_tp sched_overutilized_tp t:tracepoints/_9p_client_req 9p_client_req The event name is based on the tracepoint name, but if it is started with digit character, an underscore '_' will be added. NOTE: to avoid further confusion, this renames TPARG_FL_TPOINT to TPARG_FL_TEVENT because this flag is used for eprobe (trace-event probe). And reuse TPARG_FL_TPOINT for this raw tracepoint probe. Link: https://lore.kernel.org/all/168507471874.913472.17214624519622959593.stgit@mhiramat.roam.corp.google.com/ Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/oe-kbuild-all/202305020453.afTJ3VVp-lkp@intel.com/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-02-24kernel/trace: extract common part in process_fetch_insnSong Chen1-20/+6
Each probe has an instance of process_fetch_insn respectively, but they have something in common. This patch aims to extract the common part into process_common_fetch_insn which can be shared by each probe, and they only need to focus on their special cases. Signed-off-by: Song Chen <chensong_2000@189.cn> Suggested-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
2023-02-24kernel/trace: Provide default impelentations defined in trace_probe_tmpl.hSong Chen1-53/+2
There are 6 function definitions in trace_probe_tmpl.h, they are: 1, fetch_store_strlen 2, fetch_store_string 3, fetch_store_strlen_user 4, fetch_store_string_user 5, probe_mem_read 6, probe_mem_read_user Every C file which includes trace_probe_tmpl.h has to implement them, otherwise it gets warnings and errors. However, some of them are identical, like kprobe and eprobe, as a result, there is a lot redundant code in those 2 files. This patch would like to provide default behaviors for those functions which kprobe and eprobe can share by just including trace_probe_kernel.h with trace_probe_tmpl.h together. It removes redundant code, increases readability, and more importantly, makes it easier to introduce a new feature based on trace probe (it's possible). Link: https://lore.kernel.org/all/1672382018-18347-1-git-send-email-chensong_2000@189.cn/ Signed-off-by: Song Chen <chensong_2000@189.cn> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-02-24kernel/trace: Introduce trace_probe_print_args and use it in *probesSong Chen1-1/+1
print_probe_args is currently inplemented in trace_probe_tmpl.h and included by *probes, as a result, each probe has an identical copy. This patch will move it to trace_probe.c as an new API, each probe calls it to print their args in trace file. Link: https://lore.kernel.org/all/1672382000-18304-1-git-send-email-chensong_2000@189.cn/ Signed-off-by: Song Chen <chensong_2000@189.cn> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-02-21tracing/eprobe: no need to check for negative ret value for snprintfQuanfa Fu1-8/+4
No need to check for negative return value from snprintf() as the code does not return negative values. Link: https://lore.kernel.org/all/20230109040625.3259642-1-quanfafu@gmail.com/ Signed-off-by: Quanfa Fu <quanfafu@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-20Merge tag 'trace-probes-v6.1' of ↵Linus Torvalds1-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing/probes fixes from Steven Rostedt: - Fix possible NULL pointer dereference on trace_event_file in kprobe_event_gen_test_exit() - Fix NULL pointer dereference for trace_array in kprobe_event_gen_test_exit() - Fix memory leak of filter string for eprobes - Fix a possible memory leak in rethook_alloc() - Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case which can cause a possible use-after-free - Fix warning in eprobe filter creation - Fix eprobe filter creation as it picked the wrong event for the fields * tag 'trace-probes-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/eprobe: Fix eprobe filter to make a filter correctly tracing/eprobe: Fix warning in filter creation kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case rethook: fix a potential memleak in rethook_alloc() tracing/eprobe: Fix memory leak of filter string tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit() tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit()
2022-11-20tracing: Fix race where eprobes can be called before the eventSteven Rostedt (Google)1-0/+3
The flag that tells the event to call its triggers after reading the event is set for eprobes after the eprobe is enabled. This leads to a race where the eprobe may be triggered at the beginning of the event where the record information is NULL. The eprobe then dereferences the NULL record causing a NULL kernel pointer bug. Test for a NULL record to keep this from happening. Link: https://lore.kernel.org/linux-trace-kernel/20221116192552.1066630-1-rafaelmendsr@gmail.com/ Link: https://lore.kernel.org/linux-trace-kernel/20221117214249.2addbe10@gandalf.local.home Cc: Linux Trace Kernel <linux-trace-kernel@vger.kernel.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: stable@vger.kernel.org Fixes: 7491e2c442781 ("tracing: Add a probe that attaches to trace events") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reported-by: Rafael Mendonca <rafaelmendsr@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-18tracing/eprobe: Fix eprobe filter to make a filter correctlyMasami Hiramatsu (Google)1-1/+1
Since the eprobe filter was defined based on the eprobe's trace event itself, it doesn't work correctly. Use the original trace event of the eprobe when making the filter so that the filter works correctly. Without this fix: # echo 'e syscalls/sys_enter_openat \ flags_rename=$flags:u32 if flags < 1000' >> dynamic_events # echo 1 > events/eprobes/sys_enter_openat/enable [ 114.551550] event trace: Could not enable event sys_enter_openat -bash: echo: write error: Invalid argument With this fix: # echo 'e syscalls/sys_enter_openat \ flags_rename=$flags:u32 if flags < 1000' >> dynamic_events # echo 1 > events/eprobes/sys_enter_openat/enable # tail trace cat-241 [000] ...1. 266.498449: sys_enter_openat: (syscalls.sys_enter_openat) flags_rename=0 cat-242 [000] ...1. 266.977640: sys_enter_openat: (syscalls.sys_enter_openat) flags_rename=0 Link: https://lore.kernel.org/all/166823166395.1385292.8931770640212414483.stgit@devnote3/ Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support") Reported-by: Rafael Mendonca <rafaelmendsr@gmail.com> Tested-by: Rafael Mendonca <rafaelmendsr@gmail.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-18tracing/eprobe: Fix warning in filter creationRafael Mendonca1-1/+1
The filter pointer (filterp) passed to create_filter() function must be a pointer that references a NULL pointer, otherwise, we get a warning when adding a filter option to the event probe: root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core sched/sched_stat_runtime \ runtime=$runtime:u32 if cpu < 4' >> dynamic_events [ 5034.340439] ------------[ cut here ]------------ [ 5034.341258] WARNING: CPU: 0 PID: 223 at kernel/trace/trace_events_filter.c:1939 create_filter+0x1db/0x250 [...] stripped [ 5034.345518] RIP: 0010:create_filter+0x1db/0x250 [...] stripped [ 5034.351604] Call Trace: [ 5034.351803] <TASK> [ 5034.351959] ? process_preds+0x1b40/0x1b40 [ 5034.352241] ? rcu_read_lock_bh_held+0xd0/0xd0 [ 5034.352604] ? kasan_set_track+0x29/0x40 [ 5034.352904] ? kasan_save_alloc_info+0x1f/0x30 [ 5034.353264] create_event_filter+0x38/0x50 [ 5034.353573] __trace_eprobe_create+0x16f4/0x1d20 [ 5034.353964] ? eprobe_dyn_event_release+0x360/0x360 [ 5034.354363] ? mark_held_locks+0xa6/0xf0 [ 5034.354684] ? _raw_spin_unlock_irqrestore+0x35/0x60 [ 5034.355105] ? trace_hardirqs_on+0x41/0x120 [ 5034.355417] ? _raw_spin_unlock_irqrestore+0x35/0x60 [ 5034.355751] ? __create_object+0x5b7/0xcf0 [ 5034.356027] ? lock_is_held_type+0xaf/0x120 [ 5034.356362] ? rcu_read_lock_bh_held+0xb0/0xd0 [ 5034.356716] ? rcu_read_lock_bh_held+0xd0/0xd0 [ 5034.357084] ? kasan_set_track+0x29/0x40 [ 5034.357411] ? kasan_save_alloc_info+0x1f/0x30 [ 5034.357715] ? __kasan_kmalloc+0xb8/0xc0 [ 5034.357985] ? write_comp_data+0x2f/0x90 [ 5034.358302] ? __sanitizer_cov_trace_pc+0x25/0x60 [ 5034.358691] ? argv_split+0x381/0x460 [ 5034.358949] ? write_comp_data+0x2f/0x90 [ 5034.359240] ? eprobe_dyn_event_release+0x360/0x360 [ 5034.359620] trace_probe_create+0xf6/0x110 [ 5034.359940] ? trace_probe_match_command_args+0x240/0x240 [ 5034.360376] eprobe_dyn_event_create+0x21/0x30 [ 5034.360709] create_dyn_event+0xf3/0x1a0 [ 5034.360983] trace_parse_run_command+0x1a9/0x2e0 [ 5034.361297] ? dyn_event_release+0x500/0x500 [ 5034.361591] dyn_event_write+0x39/0x50 [ 5034.361851] vfs_write+0x311/0xe50 [ 5034.362091] ? dyn_event_seq_next+0x40/0x40 [ 5034.362376] ? kernel_write+0x5b0/0x5b0 [ 5034.362637] ? write_comp_data+0x2f/0x90 [ 5034.362937] ? __sanitizer_cov_trace_pc+0x25/0x60 [ 5034.363258] ? ftrace_syscall_enter+0x544/0x840 [ 5034.363563] ? write_comp_data+0x2f/0x90 [ 5034.363837] ? __sanitizer_cov_trace_pc+0x25/0x60 [ 5034.364156] ? write_comp_data+0x2f/0x90 [ 5034.364468] ? write_comp_data+0x2f/0x90 [ 5034.364770] ksys_write+0x158/0x2a0 [ 5034.365022] ? __ia32_sys_read+0xc0/0xc0 [ 5034.365344] __x64_sys_write+0x7c/0xc0 [ 5034.365669] ? syscall_enter_from_user_mode+0x53/0x70 [ 5034.366084] do_syscall_64+0x60/0x90 [ 5034.366356] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 5034.366767] RIP: 0033:0x7ff0b43938f3 [...] stripped [ 5034.371892] </TASK> [ 5034.374720] ---[ end trace 0000000000000000 ]--- Link: https://lore.kernel.org/all/20221108202148.1020111-1-rafaelmendsr@gmail.com/ Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support") Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-18tracing/eprobe: Fix memory leak of filter stringRafael Mendonca1-0/+1
The filter string doesn't get freed when a dynamic event is deleted. If a filter is set, then memory is leaked: root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core \ sched/sched_stat_runtime runtime=$runtime:u32 if cpu < 4' >> dynamic_events root@localhost:/sys/kernel/tracing# echo "-:egroup/stat_runtime_4core" >> dynamic_events root@localhost:/sys/kernel/tracing# echo scan > /sys/kernel/debug/kmemleak [ 224.416373] kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) root@localhost:/sys/kernel/tracing# cat /sys/kernel/debug/kmemleak unreferenced object 0xffff88810156f1b8 (size 8): comm "bash", pid 224, jiffies 4294935612 (age 55.800s) hex dump (first 8 bytes): 63 70 75 20 3c 20 34 00 cpu < 4. backtrace: [<000000009f880725>] __kmem_cache_alloc_node+0x18e/0x720 [<0000000042492946>] __kmalloc+0x57/0x240 [<0000000034ea7995>] __trace_eprobe_create+0x1214/0x1d30 [<00000000d70ef730>] trace_probe_create+0xf6/0x110 [<00000000915c7b16>] eprobe_dyn_event_create+0x21/0x30 [<000000000d894386>] create_dyn_event+0xf3/0x1a0 [<00000000e9af57d5>] trace_parse_run_command+0x1a9/0x2e0 [<0000000080777f18>] dyn_event_write+0x39/0x50 [<0000000089f0ec73>] vfs_write+0x311/0xe50 [<000000003da1bdda>] ksys_write+0x158/0x2a0 [<00000000bb1e616e>] __x64_sys_write+0x7c/0xc0 [<00000000e8aef1f7>] do_syscall_64+0x60/0x90 [<00000000fe7fe8ba>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Additionally, in __trace_eprobe_create() function, if an error occurs after the call to trace_eprobe_parse_filter(), which allocates the filter string, then memory is also leaked. That can be reproduced by creating the same event probe twice: root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core \ sched/sched_stat_runtime runtime=$runtime:u32 if cpu < 4' >> dynamic_events root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core \ sched/sched_stat_runtime runtime=$runtime:u32 if cpu < 4' >> dynamic_events -bash: echo: write error: File exists root@localhost:/sys/kernel/tracing# echo scan > /sys/kernel/debug/kmemleak [ 207.871584] kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) root@localhost:/sys/kernel/tracing# cat /sys/kernel/debug/kmemleak unreferenced object 0xffff8881020d17a8 (size 8): comm "bash", pid 223, jiffies 4294938308 (age 31.000s) hex dump (first 8 bytes): 63 70 75 20 3c 20 34 00 cpu < 4. backtrace: [<000000000e4f5f31>] __kmem_cache_alloc_node+0x18e/0x720 [<0000000024f0534b>] __kmalloc+0x57/0x240 [<000000002930a28e>] __trace_eprobe_create+0x1214/0x1d30 [<0000000028387903>] trace_probe_create+0xf6/0x110 [<00000000a80d6a9f>] eprobe_dyn_event_create+0x21/0x30 [<000000007168698c>] create_dyn_event+0xf3/0x1a0 [<00000000f036bf6a>] trace_parse_run_command+0x1a9/0x2e0 [<00000000014bde8b>] dyn_event_write+0x39/0x50 [<0000000078a097f7>] vfs_write+0x311/0xe50 [<00000000996cb208>] ksys_write+0x158/0x2a0 [<00000000a3c2acb0>] __x64_sys_write+0x7c/0xc0 [<0000000006b5d698>] do_syscall_64+0x60/0x90 [<00000000780e8ecf>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fix both issues by releasing the filter string in trace_event_probe_cleanup(). Link: https://lore.kernel.org/all/20221108235738.1021467-1-rafaelmendsr@gmail.com/ Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support") Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-10-12tracing: Move duplicate code of trace_kprobe/eprobe.c into headerSteven Rostedt (Google)1-55/+5
The functions: fetch_store_strlen_user() fetch_store_strlen() fetch_store_string_user() fetch_store_string() are identical in both trace_kprobe.c and trace_eprobe.c. Move them into a new header file trace_probe_kernel.h to share it. This code will later be used by the synthetic events as well. Marked for stable as a fix for a crash in synthetic events requires it. Link: https://lkml.kernel.org/r/20221012104534.467668078@goodmis.org Cc: stable@vger.kernel.org Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Tom Zanussi <zanussi@kernel.org> Fixes: bd82631d7ccdc ("tracing: Add support for dynamic strings to synthetic events") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-27tracing/eprobe: Fix alloc event dir failed when event name no setTao Chen1-2/+1
The event dir will alloc failed when event name no set, using the command: "echo "e:esys/ syscalls/sys_enter_openat file=\$filename:string" >> dynamic_events" It seems that dir name="syscalls/sys_enter_openat" is not allowed in debugfs. So just use the "sys_enter_openat" as the event name. Link: https://lkml.kernel.org/r/1664028814-45923-1-git-send-email-chentao.kernel@linux.alibaba.com Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Linyu Yuan <quic_linyyuan@quicinc.com> Cc: Tao Chen <chentao.kernel@linux.alibaba.com Cc: stable@vger.kernel.org Fixes: 95c104c378dc ("tracing: Auto generate event name when creating a group of events") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Tao Chen <chentao.kernel@linux.alibaba.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-26tracing/eprobe: Add eprobe filter supportMasami Hiramatsu (Google)1-8/+96
Add the filter option to the event probe. This is useful if user wants to derive a new event based on the condition of the original event. E.g. echo 'e:egroup/stat_runtime_4core sched/sched_stat_runtime \ runtime=$runtime:u32 if cpu < 4' >> ../dynamic_events Then it can filter the events only on first 4 cores. Note that the fields used for 'if' must be the fields in the original events, not eprobe events. Link: https://lkml.kernel.org/r/165932114513.2850673.2592206685744598080.stgit@devnote2 Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-21tracing/eprobes: Have event probes be consistent with kprobes and uprobesSteven Rostedt (Google)1-6/+64
Currently, if a symbol "@" is attempted to be used with an event probe (eprobes), it will cause a NULL pointer dereference crash. Both kprobes and uprobes can reference data other than the main registers. Such as immediate address, symbols and the current task name. Have eprobes do the same thing. For "comm", if "comm" is used and the event being attached to does not have the "comm" field, then make it the "$comm" that kprobes has. This is consistent to the way histograms and filters work. Link: https://lkml.kernel.org/r/20220820134401.136924220@goodmis.org Cc: stable@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Tom Zanussi <zanussi@kernel.org> Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-21tracing/eprobes: Fix reading of string fieldsSteven Rostedt (Google)1-0/+21
Currently when an event probe (eprobe) hooks to a string field, it does not display it as a string, but instead as a number. This makes the field rather useless. Handle the different kinds of strings, dynamic, static, relational/dynamic etc. Now when a string field is used, the ":string" type can be used to display it: echo "e:sw sched/sched_switch comm=$next_comm:string" > dynamic_events Link: https://lkml.kernel.org/r/20220820134400.959640191@goodmis.org Cc: stable@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Tom Zanussi <zanussi@kernel.org> Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-21tracing: React to error return from traceprobe_parse_event_name()Lukas Bulwahn1-1/+1
The function traceprobe_parse_event_name() may set the first two function arguments to a non-null value and still return -EINVAL to indicate an unsuccessful completion of the function. Hence, it is not sufficient to just check the result of the two function arguments for being not null, but the return value also needs to be checked. Commit 95c104c378dc ("tracing: Auto generate event name when creating a group of events") changed the error-return-value checking of the second traceprobe_parse_event_name() invocation in __trace_eprobe_create() and removed checking the return value to jump to the error handling case. Reinstate using the return value in the error-return-value checking. Link: https://lkml.kernel.org/r/20220811071734.20700-1-lukas.bulwahn@gmail.com Fixes: 95c104c378dc ("tracing: Auto generate event name when creating a group of events") Acked-by: Linyu Yuan <quic_linyyuan@quicinc.com> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-02tracing/eprobe: Show syntax error logs in error_log fileMasami Hiramatsu (Google)1-2/+9
Show the syntax errors for event probes in error_log file as same as other dynamic events, so that user can understand what is the problem. Link: https://lkml.kernel.org/r/165932113556.2850673.3483079297896607612.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>