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KASAN: slab-out-of-bounds Write in try_module_get

Status: upstream: reported on 2026/03/02 19:08
Reported-by: syzbot+16d5985fa5c27b7d23f4@syzkaller.appspotmail.com
First crash: 101d, last: 2d10h
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: slab-out-of-bounds Write in try_module_get 22 17 1d21h 120d 0/3 upstream: reported on 2026/02/11 05:44
android-5-10 KASAN: slab-out-of-bounds Write in try_module_get 21 11 332d 404d 0/2 auto-obsoleted due to no activity on 2025/10/12 05:38
upstream KASAN: slab-out-of-bounds Write in try_module_get modules 21 4 298d 422d 0/29 auto-obsoleted due to no activity on 2025/11/15 19:20
upstream KASAN: slab-out-of-bounds Write in try_module_get (2) modules prio:high 22 241 2d10h 125d 0/29 upstream: reported on 2026/02/06 18:05
linux-6.6 KASAN: slab-out-of-bounds Write in try_module_get 21 2 4d16h 100d 0/2 upstream: reported on 2026/03/03 08:42

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: slab-out-of-bounds in atomic_inc_not_zero include/linux/atomic/atomic-instrumented.h:577 [inline]
BUG: KASAN: slab-out-of-bounds in try_module_get+0x4f/0xf0 kernel/module.c:1076
Write of size 4 at addr ffff888025247d90 by task syz.1.93/4710

CPU: 0 PID: 4710 Comm: syz.1.93 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x235/0x290 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_inc_not_zero include/linux/atomic/atomic-instrumented.h:577 [inline]
 try_module_get+0x4f/0xf0 kernel/module.c:1076
 dvb_device_open+0xf1/0x370 drivers/media/dvb-core/dvbdev.c:113
 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414
 do_dentry_open+0x7ff/0xf80 fs/open.c:826
 do_open fs/namei.c:3616 [inline]
 path_openat+0x26f5/0x2fa0 fs/namei.c:3750
 do_filp_open+0x1e2/0x410 fs/namei.c:3777
 do_sys_openat2+0x150/0x4b0 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff82f55168e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ff82d384b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ff82d3856c0 RCX: 00007ff82f55168e
RDX: 0000000000040002 RSI: 00007ff82d384c00 RDI: ffffffffffffff9c
RBP: 00007ff82d384c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007ff82f80a308 R14: 00007ff82f80a270 R15: 00007ffc5f92c0d8
 </TASK>

Allocated by task 1:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:607 [inline]
 __usb_create_hcd+0x663/0x840 drivers/usb/core/hcd.c:2601
 vhci_hcd_probe+0xff/0x370 drivers/usb/usbip/vhci_hcd.c:1376
 platform_probe+0x137/0x1c0 drivers/base/platform.c:1391
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x284/0xc80 drivers/base/dd.c:595
 __driver_probe_device+0x1ef/0x390 drivers/base/dd.c:775
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a8/0x480 drivers/base/dd.c:999
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa3a/0x1000 drivers/base/core.c:3427
 platform_device_add+0x4b9/0x820 drivers/base/platform.c:712
 vhci_hcd_init+0x3c7/0x500 drivers/usb/usbip/vhci_hcd.c:1571
 do_one_initcall+0x272/0x730 init/main.c:1316
 do_initcall_level+0x137/0x1f0 init/main.c:1389
 do_initcalls+0x4b/0x90 init/main.c:1405
 kernel_init_freeable+0x3e9/0x570 init/main.c:1629
 kernel_init+0x19/0x1b0 init/main.c:1520
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

The buggy address belongs to the object at ffff888025247d00
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 144 bytes inside of
 192-byte region [ffff888025247d00, ffff888025247dc0)
The buggy address belongs to the page:
page:ffffea00009491c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25247
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 dead000000000100 dead000000000122 ffff888016c41a00
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12c00(GFP_NOIO|__GFP_NOWARN|__GFP_NORETRY), pid 7, ts 8284863871, free_ts 0
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 __kmalloc+0x1cd/0x330 mm/slub.c:4408
 kmalloc include/linux/slab.h:612 [inline]
 usb_alloc_urb+0x3f/0x140 drivers/usb/core/urb.c:74
 usb_internal_control_msg drivers/usb/core/message.c:109 [inline]
 usb_control_msg+0x115/0x3e0 drivers/usb/core/message.c:166
 get_port_status drivers/usb/core/hub.c:596 [inline]
 hub_ext_port_status+0x103/0x6d0 drivers/usb/core/hub.c:613
 hub_port_status drivers/usb/core/hub.c:635 [inline]
 hub_activate+0x6e9/0x1a30 drivers/usb/core/hub.c:1146
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888025247c80: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888025247d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888025247d80: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff888025247e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888025247e80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/09 09:38 linux-5.15.y dc027a595035 656e94c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Write in try_module_get
2026/06/06 08:36 linux-5.15.y dc027a595035 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Write in try_module_get
2026/05/26 03:41 linux-5.15.y 241d66fa280c c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Write in try_module_get
2026/05/11 18:05 linux-5.15.y de8dfb3f0278 845acb1c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Write in try_module_get
2026/04/10 01:02 linux-5.15.y 91d48252ad4b 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Write in try_module_get
2026/03/02 19:10 linux-5.15.y 3330a8d33e08 b9dd6534 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Write in try_module_get
2026/03/02 19:07 linux-5.15.y 3330a8d33e08 b9dd6534 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Write in try_module_get
2026/05/26 04:06 linux-5.15.y 241d66fa280c c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan general protection fault in try_module_get
* Struck through repros no longer work on HEAD.