Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'driver-core-3.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fixes from Greg KH:
"Well, one drivercore fix for kernfs to resolve a reported issue with
sysfs files being updated from atomic contexts, and another lz4 bugfix
for testing potential buffer overflows"
* tag 'driver-core-3.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
lz4: add overrun checks to lz4_uncompress_unknownoutputsize()
kernfs: kernfs_notify() must be useable from non-sleepable contexts
+61
-15
+55
-14
fs/kernfs/file.c
+55
-14
fs/kernfs/file.c
···
39
39
struct list_head files; /* goes through kernfs_open_file.list */
40
40
};
41
41
42
+
/*
43
+
* kernfs_notify() may be called from any context and bounces notifications
44
+
* through a work item. To minimize space overhead in kernfs_node, the
45
+
* pending queue is implemented as a singly linked list of kernfs_nodes.
46
+
* The list is terminated with the self pointer so that whether a
47
+
* kernfs_node is on the list or not can be determined by testing the next
48
+
* pointer for NULL.
49
+
*/
50
+
#define KERNFS_NOTIFY_EOL ((void *)&kernfs_notify_list)
51
+
52
+
static DEFINE_SPINLOCK(kernfs_notify_lock);
53
+
static struct kernfs_node *kernfs_notify_list = KERNFS_NOTIFY_EOL;
54
+
42
55
static struct kernfs_open_file *kernfs_of(struct file *file)
43
56
{
44
57
return ((struct seq_file *)file->private_data)->private;
···
796
783
return DEFAULT_POLLMASK|POLLERR|POLLPRI;
797
784
}
798
785
799
-
/**
800
-
* kernfs_notify - notify a kernfs file
801
-
* @kn: file to notify
802
-
*
803
-
* Notify @kn such that poll(2) on @kn wakes up.
804
-
*/
805
-
void kernfs_notify(struct kernfs_node *kn)
786
+
static void kernfs_notify_workfn(struct work_struct *work)
806
787
{
807
-
struct kernfs_root *root = kernfs_root(kn);
788
+
struct kernfs_node *kn;
808
789
struct kernfs_open_node *on;
809
790
struct kernfs_super_info *info;
810
-
unsigned long flags;
811
-
812
-
if (WARN_ON(kernfs_type(kn) != KERNFS_FILE))
791
+
repeat:
792
+
/* pop one off the notify_list */
793
+
spin_lock_irq(&kernfs_notify_lock);
794
+
kn = kernfs_notify_list;
795
+
if (kn == KERNFS_NOTIFY_EOL) {
796
+
spin_unlock_irq(&kernfs_notify_lock);
813
797
return;
798
+
}
799
+
kernfs_notify_list = kn->attr.notify_next;
800
+
kn->attr.notify_next = NULL;
801
+
spin_unlock_irq(&kernfs_notify_lock);
814
802
815
803
/* kick poll */
816
-
spin_lock_irqsave(&kernfs_open_node_lock, flags);
804
+
spin_lock_irq(&kernfs_open_node_lock);
817
805
818
806
on = kn->attr.open;
819
807
if (on) {
···
822
808
wake_up_interruptible(&on->poll);
823
809
}
824
810
825
-
spin_unlock_irqrestore(&kernfs_open_node_lock, flags);
811
+
spin_unlock_irq(&kernfs_open_node_lock);
826
812
827
813
/* kick fsnotify */
828
814
mutex_lock(&kernfs_mutex);
829
815
830
-
list_for_each_entry(info, &root->supers, node) {
816
+
list_for_each_entry(info, &kernfs_root(kn)->supers, node) {
831
817
struct inode *inode;
832
818
struct dentry *dentry;
833
819
···
847
833
}
848
834
849
835
mutex_unlock(&kernfs_mutex);
836
+
kernfs_put(kn);
837
+
goto repeat;
838
+
}
839
+
840
+
/**
841
+
* kernfs_notify - notify a kernfs file
842
+
* @kn: file to notify
843
+
*
844
+
* Notify @kn such that poll(2) on @kn wakes up. Maybe be called from any
845
+
* context.
846
+
*/
847
+
void kernfs_notify(struct kernfs_node *kn)
848
+
{
849
+
static DECLARE_WORK(kernfs_notify_work, kernfs_notify_workfn);
850
+
unsigned long flags;
851
+
852
+
if (WARN_ON(kernfs_type(kn) != KERNFS_FILE))
853
+
return;
854
+
855
+
spin_lock_irqsave(&kernfs_notify_lock, flags);
856
+
if (!kn->attr.notify_next) {
857
+
kernfs_get(kn);
858
+
kn->attr.notify_next = kernfs_notify_list;
859
+
kernfs_notify_list = kn;
860
+
schedule_work(&kernfs_notify_work);
861
+
}
862
+
spin_unlock_irqrestore(&kernfs_notify_lock, flags);
850
863
}
851
864
EXPORT_SYMBOL_GPL(kernfs_notify);
852
865
+1
include/linux/kernfs.h
+1
include/linux/kernfs.h
+5
-1
lib/lz4/lz4_decompress.c
+5
-1
lib/lz4/lz4_decompress.c
···
192
192
int s = 255;
193
193
while ((ip < iend) && (s == 255)) {
194
194
s = *ip++;
195
+
if (unlikely(length > (size_t)(length + s)))
196
+
goto _output_error;
195
197
length += s;
196
198
}
197
199
}
···
234
232
if (length == ML_MASK) {
235
233
while (ip < iend) {
236
234
int s = *ip++;
235
+
if (unlikely(length > (size_t)(length + s)))
236
+
goto _output_error;
237
237
length += s;
238
238
if (s == 255)
239
239
continue;
···
288
284
289
285
/* write overflow error detected */
290
286
_output_error:
291
-
return (int) (-(((char *) ip) - source));
287
+
return -1;
292
288
}
293
289
294
290
int lz4_decompress(const unsigned char *src, size_t *src_len,