[Intel-gfx] [PATCH] drm/i915/dp: fix memory leak of panel->vbt.lfp_lvds_vbt_mode

[Yongxin Liu]

In commit 3f9ffce5765d ("drm/i915: Do panel VBT init early if the VBT
declares an explicit panel type"), intel_bios_init_panel_early() was
added to intel_edp_init_connector(), and it may call parse_lfp_panel_dtd()
to alloc memory for panel->vbt.lfp_lvds_vbt_mode.

If intel_edp_init_connector() returns false from lable out_vdd_off, the
memory pointed by panel->vbt.lfp_lvds_vbt_mode will be eventually lost by
kfree(connector) in intel_ddi_init_dp_connector().

Fix the following memory leak.

unreferenced object 0xffff9e076562f100 (size 128):
  comm "modprobe", pid 365, jiffies 4294749388 (age 73.473s)
  hex dump (first 32 bytes):
    14 44 02 00 80 07 d8 07 05 08 98 08 00 00 38 04  .D............8.
    3b 04 41 04 65 04 00 00 0a 00 00 00 00 00 00 00  ;.A.e...........
  backtrace:
    [<ffffffff99dd1386>] __kmem_cache_alloc_node+0x1e6/0x3d0
    [<ffffffff99d4754a>] kmalloc_trace+0x2a/0xf0
    [<ffffffffc0b50a39>] parse_lfp_data+0x1a9/0x300 [i915]
    [<ffffffffc0b52af1>] intel_bios_init_panel+0x131/0x3d0 [i915]
    [<ffffffffc0b52db3>] intel_bios_init_panel_early+0x13/0x20 [i915]
    [<ffffffffc0c0d342>] intel_edp_init_connector+0xb2/0x620 [i915]
    [<ffffffffc0c13267>] intel_dp_init_connector+0x277/0x490 [i915]
    [<ffffffffc0c01a87>] intel_ddi_init+0x877/0xd70 [i915]
    [<ffffffffc0b6fced>] intel_setup_outputs+0x79d/0xbc0 [i915]
    [<ffffffffc0b7dce1>] intel_modeset_init_nogem+0x1a1/0x300 [i915]
    [<ffffffffc0a85b2d>] i915_driver_probe+0x2cd/0x580 [i915]
    [<ffffffffc0a900bd>] i915_pci_probe+0xcd/0x150 [i915]
    [<ffffffff9a425334>] local_pci_probe+0x44/0xa0
    [<ffffffff9a425fc4>] pci_call_probe+0x54/0x160
    [<ffffffff9a4270ae>] pci_device_probe+0x7e/0x100
    [<ffffffff9a5ec997>] really_probe+0x197/0x3c0

Fixes: 3f9ffce5765d ("drm/i915: Do panel VBT init early if the VBT declares an explicit panel type")
Signed-off-by: Yongxin Liu <yongxin.liu at windriver.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 529ee22be872..b83d14c0f1ff 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5439,6 +5439,7 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
 
 out_vdd_off:
 	intel_pps_vdd_off_sync(intel_dp);
+	intel_bios_fini_panel(&intel_connector->panel);
 
 	return false;
 }
-- 
2.39.2