redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

tracing/probe: Fix memleak in fetch_op_data operations 

commit 3aa8fdc37d upstream.

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.

Link: https://lkml.kernel.org/r/20200615143034.GA1734@cosmos

Cc: stable@vger.kernel.org
Fixes: a42e3c4de9 ("tracing/probe: Add immediate string parameter support")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5.4-rM2-2.2.x-imx-squashed
Vamshi K Sthambamkadi 2020-06-15 20:00:38 +05:30 committed by Greg Kroah-Hartman
parent 7bb62d0cd8
commit f4748ee4fa
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
kernel/trace/trace_probe.c
View File

@ -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