--- /dev/null
+From yi.zhang@huawei.com Sat Apr 24 16:48:28 2021
+From: Zhang Yi <yi.zhang@huawei.com>
+Date: Fri, 23 Apr 2021 20:37:50 +0800
+Subject: ext4: correct error label in ext4_rename()
+To: <stable@vger.kernel.org>
+Cc: <gregkh@linuxfoundation.org>, <tytso@mit.edu>, <sashal@kernel.org>, <yi.zhang@huawei.com>
+Message-ID: <20210423123750.1946580-1-yi.zhang@huawei.com>
+
+From: Zhang Yi <yi.zhang@huawei.com>
+
+The backport of upstream patch 5dccdc5a1916 ("ext4: do not iput inode
+under running transaction in ext4_rename()") introduced a regression on
+the stable kernels 4.14 and older. One of the end_rename error label was
+forgetting to change to release_bh, which may trigger below bug.
+
+ ------------[ cut here ]------------
+ kernel BUG at /home/zhangyi/hulk-4.4/fs/ext4/ext4_jbd2.c:30!
+ ...
+ Call Trace:
+ [<ffffffff8b4207b2>] ext4_rename+0x9e2/0x10c0
+ [<ffffffff8b331324>] ? unlazy_walk+0x124/0x2a0
+ [<ffffffff8b420eb5>] ext4_rename2+0x25/0x60
+ [<ffffffff8b335104>] vfs_rename+0x3a4/0xed0
+ [<ffffffff8b33a7ad>] SYSC_renameat2+0x57d/0x7f0
+ [<ffffffff8b33c119>] SyS_renameat+0x19/0x30
+ [<ffffffff8bc57bb8>] entry_SYSCALL_64_fastpath+0x18/0x78
+ ...
+ ---[ end trace 75346ce7c76b9f06 ]---
+
+Fixes: f5337ec530a6 ("ext4: do not iput inode under running transaction in ext4_rename()")
+Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/ext4/namei.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/fs/ext4/namei.c
++++ b/fs/ext4/namei.c
+@@ -3621,7 +3621,7 @@ static int ext4_rename(struct inode *old
+ ext4_encrypted_inode(new.dir) &&
+ !fscrypt_has_permitted_context(new.dir, old.inode)) {
+ retval = -EXDEV;
+- goto end_rename;
++ goto release_bh;
+ }
+
+ new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
--- /dev/null
+From foo@baz Sat Apr 24 04:46:08 PM CEST 2021
+From: Anirudh Rayabharam <mail@anirudhrb.com>
+Date: Wed, 7 Apr 2021 22:57:22 +0530
+Subject: net: hso: fix null-ptr-deref during tty device unregistration
+
+From: Anirudh Rayabharam <mail@anirudhrb.com>
+
+commit 8a12f8836145ffe37e9c8733dce18c22fb668b66 upstream
+
+Multiple ttys try to claim the same the minor number causing a double
+unregistration of the same device. The first unregistration succeeds
+but the next one results in a null-ptr-deref.
+
+The get_free_serial_index() function returns an available minor number
+but doesn't assign it immediately. The assignment is done by the caller
+later. But before this assignment, calls to get_free_serial_index()
+would return the same minor number.
+
+Fix this by modifying get_free_serial_index to assign the minor number
+immediately after one is found to be and rename it to obtain_minor()
+to better reflect what it does. Similary, rename set_serial_by_index()
+to release_minor() and modify it to free up the minor number of the
+given hso_serial. Every obtain_minor() should have corresponding
+release_minor() call.
+
+Fixes: 72dc1c096c705 ("HSO: add option hso driver")
+Reported-by: syzbot+c49fe6089f295a05e6f8@syzkaller.appspotmail.com
+Tested-by: syzbot+c49fe6089f295a05e6f8@syzkaller.appspotmail.com
+Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+[sudip: adjust context]
+Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/usb/hso.c | 33 ++++++++++++---------------------
+ 1 file changed, 12 insertions(+), 21 deletions(-)
+
+--- a/drivers/net/usb/hso.c
++++ b/drivers/net/usb/hso.c
+@@ -626,7 +626,7 @@ static struct hso_serial *get_serial_by_
+ return serial;
+ }
+
+-static int get_free_serial_index(void)
++static int obtain_minor(struct hso_serial *serial)
+ {
+ int index;
+ unsigned long flags;
+@@ -634,8 +634,10 @@ static int get_free_serial_index(void)
+ spin_lock_irqsave(&serial_table_lock, flags);
+ for (index = 0; index < HSO_SERIAL_TTY_MINORS; index++) {
+ if (serial_table[index] == NULL) {
++ serial_table[index] = serial->parent;
++ serial->minor = index;
+ spin_unlock_irqrestore(&serial_table_lock, flags);
+- return index;
++ return 0;
+ }
+ }
+ spin_unlock_irqrestore(&serial_table_lock, flags);
+@@ -644,15 +646,12 @@ static int get_free_serial_index(void)
+ return -1;
+ }
+
+-static void set_serial_by_index(unsigned index, struct hso_serial *serial)
++static void release_minor(struct hso_serial *serial)
+ {
+ unsigned long flags;
+
+ spin_lock_irqsave(&serial_table_lock, flags);
+- if (serial)
+- serial_table[index] = serial->parent;
+- else
+- serial_table[index] = NULL;
++ serial_table[serial->minor] = NULL;
+ spin_unlock_irqrestore(&serial_table_lock, flags);
+ }
+
+@@ -2243,6 +2242,7 @@ static int hso_stop_serial_device(struct
+ static void hso_serial_tty_unregister(struct hso_serial *serial)
+ {
+ tty_unregister_device(tty_drv, serial->minor);
++ release_minor(serial);
+ }
+
+ static void hso_serial_common_free(struct hso_serial *serial)
+@@ -2267,25 +2267,23 @@ static int hso_serial_common_create(stru
+ int rx_size, int tx_size)
+ {
+ struct device *dev;
+- int minor;
+ int i;
+
+ tty_port_init(&serial->port);
+
+- minor = get_free_serial_index();
+- if (minor < 0)
++ if (obtain_minor(serial))
+ goto exit2;
+
+ /* register our minor number */
+ serial->parent->dev = tty_port_register_device_attr(&serial->port,
+- tty_drv, minor, &serial->parent->interface->dev,
++ tty_drv, serial->minor, &serial->parent->interface->dev,
+ serial->parent, hso_serial_dev_groups);
+- if (IS_ERR(serial->parent->dev))
++ if (IS_ERR(serial->parent->dev)) {
++ release_minor(serial);
+ goto exit2;
++ }
+ dev = serial->parent->dev;
+
+- /* fill in specific data for later use */
+- serial->minor = minor;
+ serial->magic = HSO_SERIAL_MAGIC;
+ spin_lock_init(&serial->serial_lock);
+ serial->num_rx_urbs = num_urbs;
+@@ -2678,9 +2676,6 @@ static struct hso_device *hso_create_bul
+
+ serial->write_data = hso_std_serial_write_data;
+
+- /* and record this serial */
+- set_serial_by_index(serial->minor, serial);
+-
+ /* setup the proc dirs and files if needed */
+ hso_log_port(hso_dev);
+
+@@ -2737,9 +2732,6 @@ struct hso_device *hso_create_mux_serial
+ serial->shared_int->ref_count++;
+ mutex_unlock(&serial->shared_int->shared_int_lock);
+
+- /* and record this serial */
+- set_serial_by_index(serial->minor, serial);
+-
+ /* setup the proc dirs and files if needed */
+ hso_log_port(hso_dev);
+
+@@ -3124,7 +3116,6 @@ static void hso_free_interface(struct us
+ cancel_work_sync(&serial_table[i]->async_get_intf);
+ hso_serial_tty_unregister(serial);
+ kref_put(&serial_table[i]->ref, hso_serial_ref_free);
+- set_serial_by_index(i, NULL);
+ }
+ }
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
