| Message ID | 20230727150534.397532-1-ykaliuta@redhat.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | tracing: perf_call_bpf: use struct trace_entry in struct syscall_tp_t | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
Resending with proper subject. >>>>> On Thu, 27 Jul 2023 18:05:34 +0300, Yauheni Kaliuta wrote: > bpf tracepoint program uses struct trace_event_raw_sys_enter as > argument where trace_entry is the first field. Use the same instead > of unsigned long long since if it's amended (for example by RT > patch) it accesses data with wrong offset. > Signed-off-by: Yauheni Kaliuta <ykaliuta@redhat.com> > --- > kernel/trace/trace_syscalls.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c > index 942ddbdace4a..07f4fa395e99 100644 > --- a/kernel/trace/trace_syscalls.c > +++ b/kernel/trace/trace_syscalls.c > @@ -555,12 +555,15 @@ static int perf_call_bpf_enter(struct trace_event_call *call, struct pt_regs *re > struct syscall_trace_enter *rec) > { > struct syscall_tp_t { > - unsigned long long regs; > + struct trace_entry ent; > unsigned long syscall_nr; > unsigned long args[SYSCALL_DEFINE_MAXARGS]; > } param; > int i; > + BUILD_BUG_ON(sizeof(param.ent) < sizeof(void *)); > + > + /* __bpf_prog_run() requires *regs as the first parameter */ > *(struct pt_regs **)¶m = regs; > param.syscall_nr = rec->nr; > for (i = 0; i < sys_data->nb_args; i++) > @@ -657,11 +660,14 @@ static int perf_call_bpf_exit(struct trace_event_call *call, struct pt_regs *reg > struct syscall_trace_exit *rec) > { > struct syscall_tp_t { > - unsigned long long regs; > + struct trace_entry ent; > unsigned long syscall_nr; > unsigned long ret; > } param; > + BUILD_BUG_ON(sizeof(param.ent) < sizeof(void *)); > + > + /* __bpf_prog_run() requires *regs as the first parameter */ > *(struct pt_regs **)¶m = regs; > param.syscall_nr = rec->nr; > param.ret = rec->ret; > -- > 2.41.0
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 942ddbdace4a..07f4fa395e99 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -555,12 +555,15 @@ static int perf_call_bpf_enter(struct trace_event_call *call, struct pt_regs *re struct syscall_trace_enter *rec) { struct syscall_tp_t { - unsigned long long regs; + struct trace_entry ent; unsigned long syscall_nr; unsigned long args[SYSCALL_DEFINE_MAXARGS]; } param; int i; + BUILD_BUG_ON(sizeof(param.ent) < sizeof(void *)); + + /* __bpf_prog_run() requires *regs as the first parameter */ *(struct pt_regs **)¶m = regs; param.syscall_nr = rec->nr; for (i = 0; i < sys_data->nb_args; i++) @@ -657,11 +660,14 @@ static int perf_call_bpf_exit(struct trace_event_call *call, struct pt_regs *reg struct syscall_trace_exit *rec) { struct syscall_tp_t { - unsigned long long regs; + struct trace_entry ent; unsigned long syscall_nr; unsigned long ret; } param; + BUILD_BUG_ON(sizeof(param.ent) < sizeof(void *)); + + /* __bpf_prog_run() requires *regs as the first parameter */ *(struct pt_regs **)¶m = regs; param.syscall_nr = rec->nr; param.ret = rec->ret;
bpf tracepoint program uses struct trace_event_raw_sys_enter as argument where trace_entry is the first field. Use the same instead of unsigned long long since if it's amended (for example by RT patch) it accesses data with wrong offset. Signed-off-by: Yauheni Kaliuta <ykaliuta@redhat.com> --- kernel/trace/trace_syscalls.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)