[PATCH] drm/i915/display: Fix lfp_vbt_mode memory leak

[José Roberto de Souza]

In case anything in intel_edp_init_connector() after
intel_bios_init_panel_early() causes connector initialization to fail,
it leaks lfp_vbt_mode allocated in:
intel_bios_init_panel_early()
	intel_bios_init_panel()
		parse_lfp_data()
			parse_lfp_panel_dtd()
				panel_fixed_mode = kzalloc();
				panel->vbt.lfp_vbt_mode = panel_fixed_mode;

So here adding intel_bios_fini_panel() to the error path to free
this memory.

root at DUT147LNL:/home/gta# more /sys/kernel/debug/kmemleak
unreferenced object 0xffff88811832da00 (size 128):
  comm "modprobe", pid 1134, jiffies 4294792711
  hex dump (first 32 bytes):
    e8 fd 00 00 00 04 18 04 a0 04 40 05 00 00 00 03  .......... at .....
    03 03 09 03 26 03 00 00 0a 00 00 00 00 00 00 00  ....&...........
  backtrace (crc 7448f6b4):
    [<ffffffff812d9db0>] __kmalloc_cache_noprof+0x270/0x330
    [<ffffffffa038e56b>] intel_bios_init_panel+0x188b/0x1c70 [xe]
    [<ffffffffa03e1594>] intel_dp_init_connector+0x544/0xf00 [xe]
    [<ffffffffa03b1afb>] intel_ddi_init+0xb5b/0xf10 [xe]
    [<ffffffffa039086c>] intel_bios_for_each_encoder+0x2c/0x40 [xe]
    [<ffffffffa03c25cf>] intel_setup_outputs+0x1ff/0x470 [xe]
    [<ffffffffa03c4b63>] intel_display_driver_probe_nogem+0x133/0x1d0 [xe]
    [<ffffffffa037b659>] xe_display_init_noaccel+0x19/0x60 [xe]
    [<ffffffffa02e19f8>] xe_device_probe+0x5c8/0x720 [xe]
    [<ffffffffa032a627>] xe_pci_probe+0x7b7/0xd30 [xe]
    [<ffffffff8172d903>] pci_device_probe+0xa3/0x170
    [<ffffffff818868a0>] really_probe+0xd0/0x320
    [<ffffffff81886b63>] __driver_probe_device+0x73/0x110
    [<ffffffff81886c1a>] driver_probe_device+0x1a/0x90
    [<ffffffff81886e2a>] __driver_attach+0xaa/0x1b0
    [<ffffffff81884685>] bus_for_each_dev+0x75/0xc0

(gdb) list *(intel_bios_init_panel+0x188b)
0xb75ab is in intel_bios_init_panel (drivers/gpu/drm/i915/display/intel_bios.c:849).
844	        panel_dvo_timing = get_lfp_dvo_timing(lfp_data,
845			                                              lfp_data_ptrs,
846			                                              panel_type);
847
848	        panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
849	        if (!panel_fixed_mode)
850		                return;
851
852	        fill_detail_timing_data(i915, panel_fixed_mode, panel_dvo_timing);
853

Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 09789d62001f7..bd644cc0336bc 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -6764,6 +6764,7 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
 	return true;
 
 out_vdd_off:
+	intel_bios_fini_panel(&intel_connector->panel);
 	intel_pps_vdd_off_sync(intel_dp);
 
 	return false;
-- 
2.46.0