diff mbox series

Backport request to fix a WARNING in input_mt_init_slots

Message ID 1724766547-24435-1-git-send-email-george.kennedy@oracle.com
State New
Headers show
Series Backport request to fix a WARNING in input_mt_init_slots | expand

Commit Message

George Kennedy Aug. 27, 2024, 1:49 p.m. UTC
Hello,

We have seen a WARNING message while fuzzing with syzkaller.


Kernel 5.15.165 on an x86_64


------------[ cut here ]------------
WARNING: CPU: 1 PID: 1592 at mm/page_alloc.c:5398 __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5398
Modules linked in:
CPU: 1 PID: 1592 Comm: syz-executor777 Not tainted 5.15.165-rc1-305-ge122be7431ef1-syzk #1
Hardware name: Red Hat KVM, BIOS 1.16.0-4.module+el8.9.0+90052+d3bf71d8 04/01/2014
RIP: 0010:__alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5398
Code: 00 48 89 44 24 58 e9 fa fc ff ff 48 89 f2 48 89 c7 44 89 c6 e8 77 32 f2 ff 49 89 c7 e9 72 fd ff ff 80 e7 20 0f 85 d8 fe ff ff <0f> 0b e9 d1 fe ff ff a9 00 00 08 00 75 48 89 da 80 e2 7f a9 00 00
RSP: 0018:ffff88801c18fb58 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000000400c0 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000017 RDI: 0000000000040dc0
RBP: 1ffff11003831f6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000017 R14: 0000000000000000 R15: 0000000000000000
FS:  00007ff8aaa97740(0000) GS:ffff888107080000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff8aa38a520 CR3: 0000000022534000 CR4: 00000000000006e0
Call Trace:
 <TASK>
 alloc_pages+0x21e/0x3d0 mm/mempolicy.c:2185
 kmalloc_order+0x31/0xb0 mm/slab_common.c:966
 kmalloc_order_trace+0x19/0xa0 mm/slab_common.c:982
 kmalloc include/linux/slab.h:596 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 input_mt_init_slots+0xf6/0x620 drivers/input/input-mt.c:49
 uinput_create_device+0x1e6/0x6e0 drivers/input/misc/uinput.c:327
 uinput_ioctl_handler.isra.0+0x46f/0x15e0 drivers/input/misc/uinput.c:870
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x199/0x220 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x6c/0xd6
RIP: 0033:0x7ff8aa38a53d
Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 73 01 c3 48 8b 0d 1b 79 2c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffc7eebe838 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff8aa38a53d
RDX: 0000000000000000 RSI: 0000000000005501 RDI: 0000000000000003
RBP: 00000000004017a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 431bde82d7b634db
R13: 00007ffc7eebe960 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
---[ end trace ced5c0b641032976 ]---

Fix commit: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=99d3bf5f7377d42f8be60a6b9cb60fb0be34dceb

Can you please backport this commit to stable kernels on 5.15.y (and 
other stable kernels 6.1.y, 6.6.y)

commit: 99d3bf5f7377 ("Input: MT - limit max slots")

author	Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>	2024-07-29 21:51:30 +0900
committer	Linus Torvalds <torvalds@linux-foundation.org>	2024-07-29 10:44:48 -0700
commit	99d3bf5f7377d42f8be60a6b9cb60fb0be34dceb (patch)
tree	78dd9dff2065f2eaf5a9e981f84d56eed2346d10
parent	3894840a7a11aa06cc3b0d5a2d1b5f6878127903 (diff)
download	linux-99d3bf5f7377d42f8be60a6b9cb60fb0be34dceb.tar.gz
Input: MT - limit max slots
syzbot is reporting too large allocation at input_mt_init_slots(), for
num_slots is supplied from userspace using ioctl(UI_DEV_CREATE).

Since nobody knows possible max slots, this patch chose 1024.

Reported-by: syzbot <syzbot+0122fa359a69694395d5@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=0122fa359a69694395d5
Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat
-rw-r--r--	drivers/input/input-mt.c	3	
		
1 files changed, 3 insertions, 0 deletions
diff mbox series

Patch

diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c
index 14b53dac1253bf..6b04a674f832a0 100644
--- a/drivers/input/input-mt.c
+++ b/drivers/input/input-mt.c
@@ -46,6 +46,9 @@  int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots,
 		return 0;
 	if (mt)
 		return mt->num_slots != num_slots ? -EINVAL : 0;
+	/* Arbitrary limit for avoiding too large memory allocation. */
+	if (num_slots > 1024)
+		return -EINVAL;
 
 	mt = kzalloc(struct_size(mt, slots, num_slots), GFP_KERNEL);
 	if (!mt)