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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-02-14 09:04:36 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-02-14 09:04:36 +0100
commitfbd533e90d239e17d9427a6481ae60be25680cb7 (patch)
tree72f5b36af33981605eecf92da1516b9b4c37d5a6 /drivers/usb/gadget/function/f_fs.c
parentc18553956f34819e224a79c9890eba2ba0604e15 (diff)
parent754e0b0e35608ed5206d6a67a791563c631cec07 (diff)
Merge 5.17-rc4 into usb-next
We need the USB fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/gadget/function/f_fs.c')
-rw-r--r--drivers/usb/gadget/function/f_fs.c56
1 files changed, 42 insertions, 14 deletions
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 7461d27e9604..4585ee3a444a 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1711,16 +1711,24 @@ static void ffs_data_put(struct ffs_data *ffs)
static void ffs_data_closed(struct ffs_data *ffs)
{
+ struct ffs_epfile *epfiles;
+ unsigned long flags;
+
ENTER();
if (atomic_dec_and_test(&ffs->opened)) {
if (ffs->no_disconnect) {
ffs->state = FFS_DEACTIVATED;
- if (ffs->epfiles) {
- ffs_epfiles_destroy(ffs->epfiles,
- ffs->eps_count);
- ffs->epfiles = NULL;
- }
+ spin_lock_irqsave(&ffs->eps_lock, flags);
+ epfiles = ffs->epfiles;
+ ffs->epfiles = NULL;
+ spin_unlock_irqrestore(&ffs->eps_lock,
+ flags);
+
+ if (epfiles)
+ ffs_epfiles_destroy(epfiles,
+ ffs->eps_count);
+
if (ffs->setup_state == FFS_SETUP_PENDING)
__ffs_ep0_stall(ffs);
} else {
@@ -1767,14 +1775,27 @@ static struct ffs_data *ffs_data_new(const char *dev_name)
static void ffs_data_clear(struct ffs_data *ffs)
{
+ struct ffs_epfile *epfiles;
+ unsigned long flags;
+
ENTER();
ffs_closed(ffs);
BUG_ON(ffs->gadget);
- if (ffs->epfiles) {
- ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
+ spin_lock_irqsave(&ffs->eps_lock, flags);
+ epfiles = ffs->epfiles;
+ ffs->epfiles = NULL;
+ spin_unlock_irqrestore(&ffs->eps_lock, flags);
+
+ /*
+ * potential race possible between ffs_func_eps_disable
+ * & ffs_epfile_release therefore maintaining a local
+ * copy of epfile will save us from use-after-free.
+ */
+ if (epfiles) {
+ ffs_epfiles_destroy(epfiles, ffs->eps_count);
ffs->epfiles = NULL;
}
@@ -1922,12 +1943,15 @@ static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
static void ffs_func_eps_disable(struct ffs_function *func)
{
- struct ffs_ep *ep = func->eps;
- struct ffs_epfile *epfile = func->ffs->epfiles;
- unsigned count = func->ffs->eps_count;
+ struct ffs_ep *ep;
+ struct ffs_epfile *epfile;
+ unsigned short count;
unsigned long flags;
spin_lock_irqsave(&func->ffs->eps_lock, flags);
+ count = func->ffs->eps_count;
+ epfile = func->ffs->epfiles;
+ ep = func->eps;
while (count--) {
/* pending requests get nuked */
if (ep->ep)
@@ -1945,14 +1969,18 @@ static void ffs_func_eps_disable(struct ffs_function *func)
static int ffs_func_eps_enable(struct ffs_function *func)
{
- struct ffs_data *ffs = func->ffs;
- struct ffs_ep *ep = func->eps;
- struct ffs_epfile *epfile = ffs->epfiles;
- unsigned count = ffs->eps_count;
+ struct ffs_data *ffs;
+ struct ffs_ep *ep;
+ struct ffs_epfile *epfile;
+ unsigned short count;
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&func->ffs->eps_lock, flags);
+ ffs = func->ffs;
+ ep = func->eps;
+ epfile = ffs->epfiles;
+ count = ffs->eps_count;
while(count--) {
ep->ep->driver_data = ep;