[patch 1/2 -resend] dma-debug: debugfs_create_bool() takes a u32pointer

From: Dan Carpenter
Date: Wed Jun 27 2012 - 05:09:36 EST


Even though it has "bool" in the name, you have pass a u32 pointer to
debugfs_create_bool(). Otherwise you get memory corruption in
write_file_bool(). Fortunately in this case the corruption happens in
an alignment hole between variables so it doesn't cause any problems.

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
This was sent on Fri, 2 Mar 2012.

It's probably my fault the bug is still there. I submitted the patch
but the feed back was that debugfs_create_bool() has a stupid API and
should take a pointer to a bool. I said that yes, probably that is true
but only two places use the current API incorrectly and I fixed the
other place as well.

I assumed that both my patches would be merged and the person who cared
about API would fix the API but neither of my fixes were applied.

diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 518aea7..66ce414 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -78,7 +78,7 @@ static LIST_HEAD(free_entries);
static DEFINE_SPINLOCK(free_entries_lock);

/* Global disable flag - will be set in case of an error */
-static bool global_disable __read_mostly;
+static u32 global_disable __read_mostly;

/* Global error count */
static u32 error_count;
@@ -657,7 +657,7 @@ static int dma_debug_fs_init(void)

global_disable_dent = debugfs_create_bool("disabled", 0444,
dma_debug_dent,
- (u32 *)&global_disable);
+ &global_disable);
if (!global_disable_dent)
goto out_err;

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