| From 416dacb819f59180e4d86a5550052033ebb6d72c Mon Sep 17 00:00:00 2001 |
| From: Alan Stern <stern@rowland.harvard.edu> |
| Date: Wed, 21 Aug 2019 13:27:12 -0400 |
| Subject: HID: hidraw: Fix invalid read in hidraw_ioctl |
| |
| From: Alan Stern <stern@rowland.harvard.edu> |
| |
| commit 416dacb819f59180e4d86a5550052033ebb6d72c upstream. |
| |
| The syzbot fuzzer has reported a pair of problems in the |
| hidraw_ioctl() function: slab-out-of-bounds read and use-after-free |
| read. An example of the first: |
| |
| BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525 |
| Read of size 1 at addr ffff8881c8035f38 by task syz-executor.4/2833 |
| |
| CPU: 1 PID: 2833 Comm: syz-executor.4 Not tainted 5.3.0-rc2+ #1 |
| Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS |
| Google 01/01/2011 |
| Call Trace: |
| __dump_stack lib/dump_stack.c:77 [inline] |
| dump_stack+0xca/0x13e lib/dump_stack.c:113 |
| print_address_description+0x6a/0x32c mm/kasan/report.c:351 |
| __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482 |
| kasan_report+0xe/0x12 mm/kasan/common.c:612 |
| strlen+0x79/0x90 lib/string.c:525 |
| strlen include/linux/string.h:281 [inline] |
| hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446 |
| vfs_ioctl fs/ioctl.c:46 [inline] |
| file_ioctl fs/ioctl.c:509 [inline] |
| do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696 |
| ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713 |
| __do_sys_ioctl fs/ioctl.c:720 [inline] |
| __se_sys_ioctl fs/ioctl.c:718 [inline] |
| __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718 |
| do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296 |
| entry_SYSCALL_64_after_hwframe+0x49/0xbe |
| RIP: 0033:0x459829 |
| Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 |
| 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff |
| ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 |
| RSP: 002b:00007f7a68f6dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 |
| RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829 |
| RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004 |
| RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 |
| R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7a68f6e6d4 |
| R13: 00000000004c21de R14: 00000000004d5620 R15: 00000000ffffffff |
| |
| The two problems have the same cause: hidraw_ioctl() fails to test |
| whether the device has been removed. This patch adds the missing test. |
| |
| Reported-and-tested-by: syzbot+5a6c4ec678a0c6ee84ba@syzkaller.appspotmail.com |
| Signed-off-by: Alan Stern <stern@rowland.harvard.edu> |
| CC: <stable@vger.kernel.org> |
| Signed-off-by: Jiri Kosina <jkosina@suse.cz> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/hid/hidraw.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/drivers/hid/hidraw.c |
| +++ b/drivers/hid/hidraw.c |
| @@ -370,7 +370,7 @@ static long hidraw_ioctl(struct file *fi |
| |
| mutex_lock(&minors_lock); |
| dev = hidraw_table[minor]; |
| - if (!dev) { |
| + if (!dev || !dev->exist) { |
| ret = -ENODEV; |
| goto out; |
| } |