[PATCH] dma-buf: propagate errors from dma_buf_describe() on debugfs read
On 19 June 2016 at 10:45, Daniel Vetter wrote: > On Fri, Jun 17, 2016 at 08:57:03PM +0200, Mathias Krause wrote: >> diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c >> index 6355ab38d630..0f2a4592fdd2 100644 >> --- a/drivers/dma-buf/dma-buf.c >> +++ b/drivers/dma-buf/dma-buf.c >> @@ -881,10 +881,9 @@ static int dma_buf_describe(struct seq_file *s) >> >> static int dma_buf_show(struct seq_file *s, void *unused) >> { >> - void (*func)(struct seq_file *) = s->private; >> + int (*func)(struct seq_file *) = s->private; >> >> - func(s); >> - return 0; >> + return func(s); > > Probably even better to just nuke that indirection. Set this pointer to > NULL and inline dma_buf_describe into dma_buf_show. Even further, we can get rid of dma_buf_debugfs_create_file() too as it's only used to create this indirection. I'll send a v2 just doing that. Thanks, Mathias
[PATCH] dma-buf: propagate errors from dma_buf_describe() on debugfs read
On Fri, Jun 17, 2016 at 08:57:03PM +0200, Mathias Krause wrote: > 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 casting the function pointer to the correct type and > propagate its return value. > > This type mismatch was caught by the PaX RAP plugin. > > Signed-off-by: Mathias Krause > Cc: Sumit Semwal > Cc: Daniel Vetter > Cc: PaX Team > --- > drivers/dma-buf/dma-buf.c |5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c > index 6355ab38d630..0f2a4592fdd2 100644 > --- a/drivers/dma-buf/dma-buf.c > +++ b/drivers/dma-buf/dma-buf.c > @@ -881,10 +881,9 @@ static int dma_buf_describe(struct seq_file *s) > > static int dma_buf_show(struct seq_file *s, void *unused) > { > - void (*func)(struct seq_file *) = s->private; > + int (*func)(struct seq_file *) = s->private; > > - func(s); > - return 0; > + return func(s); Probably even better to just nuke that indirection. Set this pointer to NULL and inline dma_buf_describe into dma_buf_show. -Daniel > } > > static int dma_buf_debug_open(struct inode *inode, struct file *file) > -- > 1.7.10.4 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch
[PATCH] 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 casting the function pointer to the correct type and propagate its return value. This type mismatch was caught by the PaX RAP plugin. Signed-off-by: Mathias Krause Cc: Sumit Semwal Cc: Daniel Vetter Cc: PaX Team --- drivers/dma-buf/dma-buf.c |5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 6355ab38d630..0f2a4592fdd2 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -881,10 +881,9 @@ static int dma_buf_describe(struct seq_file *s) static int dma_buf_show(struct seq_file *s, void *unused) { - void (*func)(struct seq_file *) = s->private; + int (*func)(struct seq_file *) = s->private; - func(s); - return 0; + return func(s); } static int dma_buf_debug_open(struct inode *inode, struct file *file) -- 1.7.10.4