dma-buf: propagate errors from dma_buf_describe() on debugfs read

The callback function dma_buf_describe() returns an int not void so the
function pointer cast in dma_buf_show() is wrong. dma_buf_describe() can
also fail when acquiring the mutex gets interrupted so always returning
0 in dma_buf_show() is wrong, too.

Fix both issues by avoiding the indirection via dma_buf_show() and call
dma_buf_describe() directly. Rename it to dma_buf_debug_show() to get it
in line with the other functions.

This type mismatch was caught by the PaX RAP plugin.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: PaX Team <pageexec@freemail.hu>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
This commit is contained in:
Mathias Krause 2016-06-19 14:31:29 +02:00 committed by Sumit Semwal
parent 996818869c
commit eb0b947e3b

View File

@ -824,7 +824,7 @@ void dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr)
EXPORT_SYMBOL_GPL(dma_buf_vunmap); EXPORT_SYMBOL_GPL(dma_buf_vunmap);
#ifdef CONFIG_DEBUG_FS #ifdef CONFIG_DEBUG_FS
static int dma_buf_describe(struct seq_file *s) static int dma_buf_debug_show(struct seq_file *s, void *unused)
{ {
int ret; int ret;
struct dma_buf *buf_obj; struct dma_buf *buf_obj;
@ -879,17 +879,9 @@ static int dma_buf_describe(struct seq_file *s)
return 0; return 0;
} }
static int dma_buf_show(struct seq_file *s, void *unused)
{
void (*func)(struct seq_file *) = s->private;
func(s);
return 0;
}
static int dma_buf_debug_open(struct inode *inode, struct file *file) static int dma_buf_debug_open(struct inode *inode, struct file *file)
{ {
return single_open(file, dma_buf_show, inode->i_private); return single_open(file, dma_buf_debug_show, NULL);
} }
static const struct file_operations dma_buf_debug_fops = { static const struct file_operations dma_buf_debug_fops = {
@ -913,7 +905,7 @@ static int dma_buf_init_debugfs(void)
return err; return err;
} }
err = dma_buf_debugfs_create_file("bufinfo", dma_buf_describe); err = dma_buf_debugfs_create_file("bufinfo", NULL);
if (err) if (err)
pr_debug("dma_buf: debugfs: failed to create node bufinfo\n"); pr_debug("dma_buf: debugfs: failed to create node bufinfo\n");