[PATCH] fbcon: Fix memory leak in con2fb_release_oldinfo()

From: Masami Ichikawa
Date: Wed Apr 23 2014 - 10:36:15 EST


kmemleak reported a memory leak as below.

unreferenced object 0xffff8800dab6d8d8 (size 96):
comm "swapper/0", pid 1, jiffies 4294877598 (age 38.483s)
hex dump (first 32 bytes):
00 00 00 00 00 01 00 00 08 00 00 00 10 00 00 00 ................
07 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff814e8f2e>] kmemleak_alloc+0x4e/0xb0
[<ffffffff811a0600>] __kmalloc+0x280/0x320
[<ffffffff81309b61>] soft_cursor+0x231/0x290
[<ffffffff81309393>] bit_cursor+0x613/0x650
[<ffffffff8130556b>] fbcon_cursor+0x13b/0x1c0
[<ffffffff813755f8>] hide_cursor+0x28/0xa0
[<ffffffff81376e98>] redraw_screen+0x168/0x240
[<ffffffff81303891>] fbcon_prepare_logo+0x381/0x420
[<ffffffff81303c7e>] fbcon_init+0x34e/0x590
[<ffffffff81375828>] visual_init+0xb8/0x120
[<ffffffff81377c93>] do_bind_con_driver+0x163/0x380
[<ffffffff81378494>] do_take_over_console+0x114/0x1c0
[<ffffffff81303f23>] do_fbcon_takeover+0x63/0xd0
[<ffffffff813086dd>] fbcon_event_notify+0x68d/0x7e0
[<ffffffff814ff7ac>] notifier_call_chain+0x4c/0x70
[<ffffffff8108c85d>] __blocking_notifier_call_chain+0x4d/0x70

This memory leak cause is, fbcon_ops's cursor_src is allocated in
soft_cursor() but not released in con2fb_release_oldinfo().
so, cursor_src is needed to be released when oldinfo is going to be
released.

Signed-off-by: Masami Ichikawa <masami256@xxxxxxxxx>
---
drivers/video/console/fbcon.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index f447734..57b1d44 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -748,6 +748,7 @@ static int con2fb_release_oldinfo(struct vc_data *vc, struct fb_info *oldinfo,
fbcon_del_cursor_timer(oldinfo);
kfree(ops->cursor_state.mask);
kfree(ops->cursor_data);
+ kfree(ops->cursor_src);
kfree(ops->fontbuffer);
kfree(oldinfo->fbcon_par);
oldinfo->fbcon_par = NULL;
--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/