On Mon, 15 Jun 2020 20:00:38 +0530 Vamshi K Sthambamkadi <[email protected]> wrote:
> kmemleak report: > [<57dcc2ca>] __kmalloc_track_caller+0x139/0x2b0 > [<f1c45d0f>] kstrndup+0x37/0x80 > [<f9761eb0>] parse_probe_arg.isra.7+0x3cc/0x630 > [<055bf2ba>] traceprobe_parse_probe_arg+0x2f5/0x810 > [<655a7766>] trace_kprobe_create+0x2ca/0x950 > [<4fc6a02a>] create_or_delete_trace_kprobe+0xf/0x30 > [<6d1c8a52>] trace_run_command+0x67/0x80 > [<be812cc0>] trace_parse_run_command+0xa7/0x140 > [<aecfe401>] probes_write+0x10/0x20 > [<2027641c>] __vfs_write+0x30/0x1e0 > [<6a4aeee1>] vfs_write+0x96/0x1b0 > [<3517fb7d>] ksys_write+0x53/0xc0 > [<dad91db7>] __ia32_sys_write+0x15/0x20 > [<da347f64>] do_syscall_32_irqs_on+0x3d/0x260 > [<fd0b7e7d>] do_fast_syscall_32+0x39/0xb0 > [<ea5ae810>] entry_SYSENTER_32+0xaf/0x102 > > Post parse_probe_arg(), the FETCH_OP_DATA operation type is overwritten > to FETCH_OP_ST_STRING, as a result memory is never freed since > traceprobe_free_probe_arg() iterates only over SYMBOL and DATA op types > > Setup fetch string operation correctly after fetch_op_data operation. > Oops, Good catch! (I've commented it but not coded...) Acked-by: Masami Hiramatsu <[email protected]> And, Fixes: a42e3c4de964 ("tracing/probe: Add immediate string parameter support") Cc: [email protected] Thank you! > Signed-off-by: Vamshi K Sthambamkadi <[email protected]> > --- > kernel/trace/trace_probe.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c > index b8a928e..d2867cc 100644 > --- a/kernel/trace/trace_probe.c > +++ b/kernel/trace/trace_probe.c > @@ -639,8 +639,8 @@ static int traceprobe_parse_probe_arg_body(char *arg, > ssize_t *size, > ret = -EINVAL; > goto fail; > } > - if ((code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM) || > - parg->count) { > + if ((code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM || > + code->op == FETCH_OP_DATA) || parg->count) { > /* > * IMM, DATA and COMM is pointing actual address, those > * must be kept, and if parg->count != 0, this is an > -- > 2.7.4 > -- Masami Hiramatsu
