KASAN: invalid-free in f_uac1_opts_c_srate_store

Status: upstream: reported C repro on 2026/08/02 03:46
Subsystems: usb
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+2532c7901f590afd0c3a@syzkaller.appspotmail.com
First crash: 5d17h, last: 2d07h
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
e606b792 assessment-security DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ KASAN: invalid-free in f_uac1_opts_c_srate_store 2026/07/31 01:30 2026/07/31 01:30 2026/07/31 03:32 aaffb173 

			
				
	

	
	



			

		

	

	
	

		

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			[PATCH] usb: gadget: f_uac1/f_uac2: fix invalid-free and memory leak in sampling rate store
			1 (1)
			2026/08/02 16:28
		

	
		

			[syzbot] [usb?] KASAN: invalid-free in f_uac1_opts_c_srate_store
			0 (3)
			2026/08/02 13:27
		

	
	




			
			
		

	

	
	

		

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			android-6-12
			
				KASAN: invalid-free in f_uac1_opts_c_srate_store
			
			24
			syz, C
			
			
			3
			7d18h
			
				
					7d19h
				
			
			
			
			
				0/1
			
			
				
					
						premoderation: reported C repro on 2026/07/27 01:32
					
				
			
			
		

	
	





			
			
			
			
		

	

	
	

		

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			Last patch testing requests (2)
		

		

			
			

	

		
		
		

			
			Created
			Duration
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			Patch
			Repo
			
			Result
		

		
		
		
			

				
				2026/08/02 13:27
				
					25m
				
				
					
						subasris1210@gmail.com
					
				
				patch
				git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-linus
				
				
					
						OK
						
					
					
					
						log
					
					
					
				
			

		
			

				
				2026/08/02 12:54
				
					6m
				
				
					
						subasris1210@gmail.com
					
				
				patch
				git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git 5d5fd841c34649f1b09220fe58e59dffd61c447d
				
				
					
						error
					
					
					
					
					
				
			

		
		
	



			
			
			
		

	

	

	
	
Sample crash report:

	
==================================================================
BUG: KASAN: invalid-free in f_uac1_opts_c_srate_store+0x1d4/0x260 drivers/usb/gadget/function/f_uac1.c:1666
Free of addr ffff88803ea06993 by task syz.0.17/5915

CPU: 0 UID: 0 PID: 5915 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report_invalid_free+0xb8/0x190 mm/kasan/report.c:557
 check_slab_allocation+0xe1/0xf0 mm/kasan/common.c:230
 kasan_slab_pre_free include/linux/kasan.h:199 [inline]
 slab_free_hook mm/slub.c:2622 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x1b6/0x6c0 mm/slub.c:6692
 f_uac1_opts_c_srate_store+0x1d4/0x260 drivers/usb/gadget/function/f_uac1.c:1666
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f964059e019
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe2077f218 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f9640825fa0 RCX: 00007f964059e019
RDX: 0000000000000029 RSI: 0000200000000040 RDI: 0000000000000003
RBP: 00007f964063500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9640825fac R14: 00007f9640825fa0 R15: 00007f9640825fa0
 </TASK>

Allocated by task 5915:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5334 [inline]
 __kmalloc_node_track_caller_noprof+0x331/0x830 mm/slub.c:5471
 __kmemdup_nul mm/util.c:64 [inline]
 kstrdup+0x51/0xe0 mm/util.c:84
 f_uac1_opts_c_srate_store+0x113/0x260 drivers/usb/gadget/function/f_uac1.c:1666
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88803ea06980
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 19 bytes inside of
 42-byte region [ffff88803ea06980, ffff88803ea069aa)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88803ea06880 pfn:0x3ea06
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801bc428c0 ffffea0000d8b290 ffffea0000b89150
raw: ffff88803ea06880 000000080020001d 00000000f5000000 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 0xd2c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5794, tgid 5794 (syz-executor), ts 78142281665, free_ts 78139864775
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab mm/slub.c:3380 [inline]
 new_slab+0xa2/0x640 mm/slub.c:3426
 refill_objects+0xe3/0x410 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675
 alloc_from_pcs mm/slub.c:4773 [inline]
 slab_alloc_node mm/slub.c:4905 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 tomoyo_encode2+0xfb/0x3c0 security/tomoyo/realpath.c:45
 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x18c/0x690 security/tomoyo/realpath.c:283
 tomoyo_mount_acl+0x1b6/0x8b0 security/tomoyo/mount.c:107
 tomoyo_mount_permission+0x214/0x460 security/tomoyo/mount.c:239
 security_sb_mount+0xdd/0x270 security/security.c:1088
 path_mount+0x158/0x23d0 fs/namespace.c:4103
 do_mount fs/namespace.c:4174 [inline]
 __do_sys_mount fs/namespace.c:4390 [inline]
 __se_sys_mount fs/namespace.c:4367 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4367
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
page last free pid 5794 tgid 5794 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
 selinux_genfs_get_sid security/selinux/hooks.c:1364 [inline]
 inode_doinit_with_dentry+0x99d/0x1320 security/selinux/hooks.c:1563
 selinux_d_instantiate+0x26/0x40 security/selinux/hooks.c:6678
 security_d_instantiate+0x14c/0x1b0 security/security.c:3704
 d_splice_alias_ops+0xd7/0x15c0 fs/dcache.c:3244
 proc_sys_lookup+0x319/0x430 fs/proc/proc_sysctl.c:544
 __lookup_slow+0x155/0x320 fs/namei.c:1919
 lookup_slow+0x50/0x70 fs/namei.c:1936
 walk_component fs/namei.c:2282 [inline]
 lookup_last fs/namei.c:2789 [inline]
 path_lookupat+0x5e8/0xc40 fs/namei.c:2813
 filename_lookup+0x202/0x590 fs/namei.c:2842
 user_path_at+0x3c/0x60 fs/namei.c:3641
 do_mount fs/namespace.c:4171 [inline]
 __do_sys_mount fs/namespace.c:4390 [inline]
 __se_sys_mount fs/namespace.c:4367 [inline]
 __x64_sys_mount+0x1fb/0x310 fs/namespace.c:4367
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88803ea06880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88803ea06900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88803ea06980: 00 00 00 00 00 02 fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff88803ea06a00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88803ea06a80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================



	

	



	Crashes (4):
		
		

			Time
			Kernel
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			2026/08/01 13:59
			upstream
			02dc699f83d0
			e611ffe1
			.config
			console log
			report
			syz / log
			C
			
			
				[disk image (non-bootable)]
			
				[vmlinux]
			
				[kernel image]
			
			ci-qemu-upstream
			KASAN: invalid-free in f_uac1_opts_c_srate_store
		

		
		

			2026/07/29 03:36
			upstream
			3b5f4b83c4ab
			19622d9d
			.config
			console log
			report
			
			
			
			
				[disk image (non-bootable)]
			
				[vmlinux]
			
				[kernel image]
			
			ci-snapshot-upstream-root
			KASAN: invalid-free in f_uac1_opts_c_srate_store
		

		
		

			2026/07/31 08:02
			upstream
			3708dd948844
			aaffb173
			.config
			console log
			report
			
			
			info
			
				[disk image (non-bootable)]
			
				[vmlinux]
			
				[kernel image]
			
			ci-qemu-upstream-386
			KASAN: invalid-free in f_uac1_opts_c_srate_store
		

		
		

			2026/07/31 08:02
			upstream
			3708dd948844
			aaffb173
			.config
			console log
			report
			
			
			info
			
				[disk image (non-bootable)]
			
				[vmlinux]
			
				[kernel image]
			
			ci-qemu-upstream-386
			KASAN: invalid-free in f_uac1_opts_c_srate_store
		

		
		


* Struck through repros no longer work on HEAD.