[syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    5cd64d4f9268 Merge tag 'ceph-for-6.17-rc6' of https://gith..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16c0db12580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4d8792ecb6308d0f
dashboard link: https://syzkaller.appspot.com/bug?extid=7617e19c8a59edfbd879
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11240762580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1552db62580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3840aa3ff580/disk-5cd64d4f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/aa965f106402/vmlinux-5cd64d4f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/88839eb3c76c/bzImage-5cd64d4f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: stack-out-of-bounds in cp2112_write_req drivers/hid/hid-cp2112.c:477 [inline]
BUG: KASAN: stack-out-of-bounds in cp2112_xfer+0x713/0xf10 drivers/hid/hid-cp2112.c:692
Read of size 34 at addr ffffc90003c0fd21 by task syz.0.17/6028

CPU: 1 UID: 0 PID: 6028 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189
 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
 cp2112_write_req drivers/hid/hid-cp2112.c:477 [inline]
 cp2112_xfer+0x713/0xf10 drivers/hid/hid-cp2112.c:692
 __i2c_smbus_xfer+0x5b6/0x1e50 drivers/i2c/i2c-core-smbus.c:591
 i2c_smbus_xfer+0x275/0x3c0 drivers/i2c/i2c-core-smbus.c:546
 i2cdev_ioctl_smbus+0x43d/0x6d0 drivers/i2c/i2c-dev.c:389
 i2cdev_ioctl+0x5d3/0x7f0 drivers/i2c/i2c-dev.c:478
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f44e378eba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcb2858658 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f44e39d5fa0 RCX: 00007f44e378eba9
RDX: 0000200000000040 RSI: 0000000000000720 RDI: 0000000000000004
RBP: 00007f44e3811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f44e39d5fa0 R14: 00007f44e39d5fa0 R15: 0000000000000003
 </TASK>

The buggy address belongs to stack of task syz.0.17/6028
 and is located at offset 33 in frame:
 i2cdev_ioctl_smbus+0x0/0x6d0 drivers/i2c/i2c-dev.c:317

This frame has 1 object:
 [32, 66) 'temp'

The buggy address belongs to a vmalloc virtual mapping
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5724d
memcg:ffff888026b61482
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff ffff888026b61482
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 5953, tgid 5953 (syz.0.10), ts 82929749894, free_ts 82841187973
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline]
 alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2507
 vm_area_alloc_pages mm/vmalloc.c:3642 [inline]
 __vmalloc_area_node mm/vmalloc.c:3720 [inline]
 __vmalloc_node_range_noprof+0x97d/0x12f0 mm/vmalloc.c:3893
 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:3956
 alloc_thread_stack_node kernel/fork.c:311 [inline]
 dup_task_struct+0x3e7/0x860 kernel/fork.c:881
 copy_process+0x54b/0x3c00 kernel/fork.c:2004
 kernel_clone+0x21e/0x840 kernel/fork.c:2605
 __do_sys_clone3 kernel/fork.c:2909 [inline]
 __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2888
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5941 tgid 5941 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
 vfree+0x25a/0x400 mm/vmalloc.c:3434
 kcov_put kernel/kcov.c:439 [inline]
 kcov_close+0x28/0x50 kernel/kcov.c:535
 __fput+0x449/0xa70 fs/file_table.c:468
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x2300 kernel/exit.c:961
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffffc90003c0fc00: 00 00 00 00 f1 f1 f1 f1 00 f3 f3 f3 00 00 00 00
 ffffc90003c0fc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90003c0fd00: f1 f1 f1 f1 00 00 00 00 02 f3 f3 f3 f3 f3 f3 f3
                                           ^
 ffffc90003c0fd80: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
 ffffc90003c0fe00: 04 f2 00 00 f2 f2 00 00 f3 f3 f3 f3 00 00 00 00
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

Forwarded: Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com.

***

Subject: Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer
Author: deepak.takumi.120@gmail.com

#syz test

diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c
index 482f62a78c41..8e17500256f1 100644
--- a/drivers/hid/hid-cp2112.c
+++ b/drivers/hid/hid-cp2112.c
@@ -689,7 +689,9 @@ static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
                        count = cp2112_write_read_req(buf, addr, read_length,
                                                      command, NULL, 0);
                } else {
-                       count = cp2112_write_req(buf, addr, command,
+                       if (data->block[0] > 32)
+                               count = -EINVAL;
+                       else count = cp2112_write_req(buf, addr, command,
                                                 data->block + 1,
                                                 data->block[0]);
                }
@@ -700,7 +702,9 @@ static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
                                                      I2C_SMBUS_BLOCK_MAX,
                                                      command, NULL, 0);
                } else {
-                       count = cp2112_write_req(buf, addr, command,
+                       if (data->block[0] > 32)
+                               count = -EINVAL;
+                       else count = cp2112_write_req(buf, addr, command,
                                                 data->block,
                                                 data->block[0] + 1);
                }
@@ -709,7 +713,9 @@ static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
                size = I2C_SMBUS_BLOCK_DATA;
                read_write = I2C_SMBUS_READ;

-               count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
+               if (data->block[0] > 32)
+                       count = -EINVAL;
+               else count = cp2112_write_read_req(buf, addr,
I2C_SMBUS_BLOCK_MAX,
                                              command, data->block,
                                              data->block[0] + 1);
                break;

Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

failed to apply patch:
checking file drivers/hid/hid-cp2112.c
patch: **** unexpected end of file in patch



Tested on:

commit:         f83ec76b Linux 6.17-rc6
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=4d8792ecb6308d0f
dashboard link: https://syzkaller.appspot.com/bug?extid=7617e19c8a59edfbd879
compiler:       
patch:          https://syzkaller.appspot.com/x/patch.diff?x=15b7f934580000

Forwarded: Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com.

***

Subject: Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer
Author: deepak.takumi.120@gmail.com

#syz test
diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c
index 482f62a78c41..8e17500256f1 100644
--- a/drivers/hid/hid-cp2112.c
+++ b/drivers/hid/hid-cp2112.c
@@ -689,7 +689,9 @@ static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
                        count = cp2112_write_read_req(buf, addr, read_length,
                                                      command, NULL, 0);
                } else {
-                       count = cp2112_write_req(buf, addr, command,
+                       if (data->block[0] > 32)
+                               count = -EINVAL;
+                       else count = cp2112_write_req(buf, addr, command,
                                                 data->block + 1,
                                                 data->block[0]);
                }
@@ -700,7 +702,9 @@ static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
                                                      I2C_SMBUS_BLOCK_MAX,
                                                      command, NULL, 0);
                } else {
-                       count = cp2112_write_req(buf, addr, command,
+                       if (data->block[0] > 32)
+                               count = -EINVAL;
+                       else count = cp2112_write_req(buf, addr, command,
                                                 data->block,
                                                 data->block[0] + 1);
                }
@@ -709,7 +713,9 @@ static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
                size = I2C_SMBUS_BLOCK_DATA;
                read_write = I2C_SMBUS_READ;

-               count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
+               if (data->block[0] > 32)
+                       count = -EINVAL;
+               else count = cp2112_write_read_req(buf, addr,
I2C_SMBUS_BLOCK_MAX,
                                              command, data->block,
                                              data->block[0] + 1);
                break;
--

Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

failed to apply patch:
checking file drivers/hid/hid-cp2112.c
patch: **** unexpected end of file in patch



Tested on:

commit:         f83ec76b Linux 6.17-rc6
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=4d8792ecb6308d0f
dashboard link: https://syzkaller.appspot.com/bug?extid=7617e19c8a59edfbd879
compiler:       
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1498d762580000

Forwarded: Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com.

***

Subject: Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer
Author: deepak.takumi.120@gmail.com

#syz test


On Mon, Sep 15, 2025 at 11:48 PM syzbot
<syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com> wrote:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    5cd64d4f9268 Merge tag 'ceph-for-6.17-rc6' of https://gith..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=16c0db12580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=4d8792ecb6308d0f
> dashboard link: https://syzkaller.appspot.com/bug?extid=7617e19c8a59edfbd879
> compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11240762580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1552db62580000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/3840aa3ff580/disk-5cd64d4f.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/aa965f106402/vmlinux-5cd64d4f.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/88839eb3c76c/bzImage-5cd64d4f.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com
>
> ==================================================================
> BUG: KASAN: stack-out-of-bounds in cp2112_write_req drivers/hid/hid-cp2112.c:477 [inline]
> BUG: KASAN: stack-out-of-bounds in cp2112_xfer+0x713/0xf10 drivers/hid/hid-cp2112.c:692
> Read of size 34 at addr ffffc90003c0fd21 by task syz.0.17/6028
>
> CPU: 1 UID: 0 PID: 6028 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
> Call Trace:
>  <TASK>
>  dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
>  print_address_description mm/kasan/report.c:378 [inline]
>  print_report+0xca/0x240 mm/kasan/report.c:482
>  kasan_report+0x118/0x150 mm/kasan/report.c:595
>  check_region_inline mm/kasan/generic.c:-1 [inline]
>  kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189
>  __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
>  cp2112_write_req drivers/hid/hid-cp2112.c:477 [inline]
>  cp2112_xfer+0x713/0xf10 drivers/hid/hid-cp2112.c:692
>  __i2c_smbus_xfer+0x5b6/0x1e50 drivers/i2c/i2c-core-smbus.c:591
>  i2c_smbus_xfer+0x275/0x3c0 drivers/i2c/i2c-core-smbus.c:546
>  i2cdev_ioctl_smbus+0x43d/0x6d0 drivers/i2c/i2c-dev.c:389
>  i2cdev_ioctl+0x5d3/0x7f0 drivers/i2c/i2c-dev.c:478
>  vfs_ioctl fs/ioctl.c:51 [inline]
>  __do_sys_ioctl fs/ioctl.c:598 [inline]
>  __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
>  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
>  do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f44e378eba9
> Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007ffcb2858658 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 00007f44e39d5fa0 RCX: 00007f44e378eba9
> RDX: 0000200000000040 RSI: 0000000000000720 RDI: 0000000000000004
> RBP: 00007f44e3811e19 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007f44e39d5fa0 R14: 00007f44e39d5fa0 R15: 0000000000000003
>  </TASK>
>
> The buggy address belongs to stack of task syz.0.17/6028
>  and is located at offset 33 in frame:
>  i2cdev_ioctl_smbus+0x0/0x6d0 drivers/i2c/i2c-dev.c:317
>
> This frame has 1 object:
>  [32, 66) 'temp'
>
> The buggy address belongs to a vmalloc virtual mapping
> The buggy address belongs to the physical page:
> page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5724d
> memcg:ffff888026b61482
> flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
> raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
> raw: 0000000000000000 0000000000000000 00000001ffffffff ffff888026b61482
> page dumped because: kasan: bad access detected
> page_owner tracks the page as allocated
> page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 5953, tgid 5953 (syz.0.10), ts 82929749894, free_ts 82841187973
>  set_page_owner include/linux/page_owner.h:32 [inline]
>  post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
>  prep_new_page mm/page_alloc.c:1859 [inline]
>  get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
>  __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
>  alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
>  alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline]
>  alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2507
>  vm_area_alloc_pages mm/vmalloc.c:3642 [inline]
>  __vmalloc_area_node mm/vmalloc.c:3720 [inline]
>  __vmalloc_node_range_noprof+0x97d/0x12f0 mm/vmalloc.c:3893
>  __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:3956
>  alloc_thread_stack_node kernel/fork.c:311 [inline]
>  dup_task_struct+0x3e7/0x860 kernel/fork.c:881
>  copy_process+0x54b/0x3c00 kernel/fork.c:2004
>  kernel_clone+0x21e/0x840 kernel/fork.c:2605
>  __do_sys_clone3 kernel/fork.c:2909 [inline]
>  __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2888
>  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
>  do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
> page last free pid 5941 tgid 5941 stack trace:
>  reset_page_owner include/linux/page_owner.h:25 [inline]
>  free_pages_prepare mm/page_alloc.c:1395 [inline]
>  __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
>  vfree+0x25a/0x400 mm/vmalloc.c:3434
>  kcov_put kernel/kcov.c:439 [inline]
>  kcov_close+0x28/0x50 kernel/kcov.c:535
>  __fput+0x449/0xa70 fs/file_table.c:468
>  task_work_run+0x1d1/0x260 kernel/task_work.c:227
>  exit_task_work include/linux/task_work.h:40 [inline]
>  do_exit+0x6b5/0x2300 kernel/exit.c:961
>  do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
>  get_signal+0x1286/0x1340 kernel/signal.c:3034
>  arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
>  exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
>  exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
>  syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
>  syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
>  do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> Memory state around the buggy address:
>  ffffc90003c0fc00: 00 00 00 00 f1 f1 f1 f1 00 f3 f3 f3 00 00 00 00
>  ffffc90003c0fc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> >ffffc90003c0fd00: f1 f1 f1 f1 00 00 00 00 02 f3 f3 f3 f3 f3 f3 f3
>                                            ^
>  ffffc90003c0fd80: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>  ffffc90003c0fe00: 04 f2 00 00 f2 f2 00 00 f3 f3 f3 f3 00 00 00 00
> ==================================================================
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.
>
> If you want to overwrite report's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
>
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@googlegroups.com.
> To view this discussion visit https://groups.google.com/d/msgid/syzkaller-bugs/68c85874.050a0220.50883.0016.GAE%40google.com.

Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com
Tested-by: syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com

Tested on:

commit:         f83ec76b Linux 6.17-rc6
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=103a1762580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4d8792ecb6308d0f
dashboard link: https://syzkaller.appspot.com/bug?extid=7617e19c8a59edfbd879
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=153f947c580000

Note: testing is done by a robot and is best-effort only.

Forwarded: Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com.

***

Subject: Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer
Author: deepak.takumi.120@gmail.com

#syz test

On Mon, Sep 15, 2025 at 11:48 PM syzbot
<syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com> wrote:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    5cd64d4f9268 Merge tag 'ceph-for-6.17-rc6' of https://gith..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=16c0db12580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=4d8792ecb6308d0f
> dashboard link: https://syzkaller.appspot.com/bug?extid=7617e19c8a59edfbd879
> compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11240762580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1552db62580000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/3840aa3ff580/disk-5cd64d4f.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/aa965f106402/vmlinux-5cd64d4f.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/88839eb3c76c/bzImage-5cd64d4f.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com
>
> ==================================================================
> BUG: KASAN: stack-out-of-bounds in cp2112_write_req drivers/hid/hid-cp2112.c:477 [inline]
> BUG: KASAN: stack-out-of-bounds in cp2112_xfer+0x713/0xf10 drivers/hid/hid-cp2112.c:692
> Read of size 34 at addr ffffc90003c0fd21 by task syz.0.17/6028
>
> CPU: 1 UID: 0 PID: 6028 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
> Call Trace:
>  <TASK>
>  dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
>  print_address_description mm/kasan/report.c:378 [inline]
>  print_report+0xca/0x240 mm/kasan/report.c:482
>  kasan_report+0x118/0x150 mm/kasan/report.c:595
>  check_region_inline mm/kasan/generic.c:-1 [inline]
>  kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189
>  __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
>  cp2112_write_req drivers/hid/hid-cp2112.c:477 [inline]
>  cp2112_xfer+0x713/0xf10 drivers/hid/hid-cp2112.c:692
>  __i2c_smbus_xfer+0x5b6/0x1e50 drivers/i2c/i2c-core-smbus.c:591
>  i2c_smbus_xfer+0x275/0x3c0 drivers/i2c/i2c-core-smbus.c:546
>  i2cdev_ioctl_smbus+0x43d/0x6d0 drivers/i2c/i2c-dev.c:389
>  i2cdev_ioctl+0x5d3/0x7f0 drivers/i2c/i2c-dev.c:478
>  vfs_ioctl fs/ioctl.c:51 [inline]
>  __do_sys_ioctl fs/ioctl.c:598 [inline]
>  __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
>  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
>  do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f44e378eba9
> Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007ffcb2858658 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 00007f44e39d5fa0 RCX: 00007f44e378eba9
> RDX: 0000200000000040 RSI: 0000000000000720 RDI: 0000000000000004
> RBP: 00007f44e3811e19 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007f44e39d5fa0 R14: 00007f44e39d5fa0 R15: 0000000000000003
>  </TASK>
>
> The buggy address belongs to stack of task syz.0.17/6028
>  and is located at offset 33 in frame:
>  i2cdev_ioctl_smbus+0x0/0x6d0 drivers/i2c/i2c-dev.c:317
>
> This frame has 1 object:
>  [32, 66) 'temp'
>
> The buggy address belongs to a vmalloc virtual mapping
> The buggy address belongs to the physical page:
> page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5724d
> memcg:ffff888026b61482
> flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
> raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
> raw: 0000000000000000 0000000000000000 00000001ffffffff ffff888026b61482
> page dumped because: kasan: bad access detected
> page_owner tracks the page as allocated
> page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 5953, tgid 5953 (syz.0.10), ts 82929749894, free_ts 82841187973
>  set_page_owner include/linux/page_owner.h:32 [inline]
>  post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
>  prep_new_page mm/page_alloc.c:1859 [inline]
>  get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
>  __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
>  alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
>  alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline]
>  alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2507
>  vm_area_alloc_pages mm/vmalloc.c:3642 [inline]
>  __vmalloc_area_node mm/vmalloc.c:3720 [inline]
>  __vmalloc_node_range_noprof+0x97d/0x12f0 mm/vmalloc.c:3893
>  __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:3956
>  alloc_thread_stack_node kernel/fork.c:311 [inline]
>  dup_task_struct+0x3e7/0x860 kernel/fork.c:881
>  copy_process+0x54b/0x3c00 kernel/fork.c:2004
>  kernel_clone+0x21e/0x840 kernel/fork.c:2605
>  __do_sys_clone3 kernel/fork.c:2909 [inline]
>  __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2888
>  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
>  do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
> page last free pid 5941 tgid 5941 stack trace:
>  reset_page_owner include/linux/page_owner.h:25 [inline]
>  free_pages_prepare mm/page_alloc.c:1395 [inline]
>  __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
>  vfree+0x25a/0x400 mm/vmalloc.c:3434
>  kcov_put kernel/kcov.c:439 [inline]
>  kcov_close+0x28/0x50 kernel/kcov.c:535
>  __fput+0x449/0xa70 fs/file_table.c:468
>  task_work_run+0x1d1/0x260 kernel/task_work.c:227
>  exit_task_work include/linux/task_work.h:40 [inline]
>  do_exit+0x6b5/0x2300 kernel/exit.c:961
>  do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
>  get_signal+0x1286/0x1340 kernel/signal.c:3034
>  arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
>  exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
>  exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
>  syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
>  syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
>  do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> Memory state around the buggy address:
>  ffffc90003c0fc00: 00 00 00 00 f1 f1 f1 f1 00 f3 f3 f3 00 00 00 00
>  ffffc90003c0fc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> >ffffc90003c0fd00: f1 f1 f1 f1 00 00 00 00 02 f3 f3 f3 f3 f3 f3 f3
>                                            ^
>  ffffc90003c0fd80: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>  ffffc90003c0fe00: 04 f2 00 00 f2 f2 00 00 f3 f3 f3 f3 00 00 00 00
> ==================================================================
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.
>
> If you want to overwrite report's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
>
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@googlegroups.com.
> To view this discussion visit https://groups.google.com/d/msgid/syzkaller-bugs/68c85874.050a0220.50883.0016.GAE%40google.com.

Re: [syzbot] [input?] KASAN: stack-out-of-bounds Read in cp2112_xfer

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com
Tested-by: syzbot+7617e19c8a59edfbd879@syzkaller.appspotmail.com

Tested on:

commit:         46a51f4f Merge tag 'for-v6.17-rc' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16af8e42580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4d8792ecb6308d0f
dashboard link: https://syzkaller.appspot.com/bug?extid=7617e19c8a59edfbd879
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10350534580000

Note: testing is done by a robot and is best-effort only.