================================================================== BUG: KASAN: use-after-free in gphonet_set_gadget drivers/usb/gadget/function/f_phonet.c:720 [inline] BUG: KASAN: use-after-free in pn_bind+0x100/0x9c0 drivers/usb/gadget/function/f_phonet.c:510 Write of size 8 at addr ffff0000f53306c0 by task syz.3.413/5949 CPU: 0 PID: 5949 Comm: syz.3.413 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 print_address_description+0x88/0x218 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:420 kasan_report+0xa8/0xfc mm/kasan/report.c:524 __asan_report_store8_noabort+0x2c/0x38 mm/kasan/report_generic.c:356 gphonet_set_gadget drivers/usb/gadget/function/f_phonet.c:720 [inline] pn_bind+0x100/0x9c0 drivers/usb/gadget/function/f_phonet.c:510 usb_add_function+0x234/0x7a8 drivers/usb/gadget/composite.c:337 configfs_composite_bind+0x7e0/0xce4 drivers/usb/gadget/configfs.c:1409 gadget_bind_driver+0x26c/0x684 drivers/usb/gadget/udc/core.c:1651 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x3a0/0xac4 drivers/base/dd.c:638 __driver_probe_device+0x1c8/0x368 drivers/base/dd.c:804 driver_probe_device+0x78/0x324 drivers/base/dd.c:834 __driver_attach+0x3bc/0x614 drivers/base/dd.c:1220 bus_for_each_dev+0x148/0x1d0 drivers/base/bus.c:303 driver_attach+0x50/0x60 drivers/base/dd.c:1237 bus_add_driver+0x2c0/0x518 drivers/base/bus.c:620 driver_register+0x200/0x37c drivers/base/driver.c:246 usb_gadget_register_driver_owner+0xf0/0x25c drivers/usb/gadget/udc/core.c:1730 gadget_dev_desc_UDC_store+0x168/0x268 drivers/usb/gadget/configfs.c:290 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x260/0x338 fs/configfs/file.c:229 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x3c8/0x7c8 fs/read_write.c:584 ksys_write+0x12c/0x228 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Allocated by task 5614: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:53 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node+0xdc/0x184 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x88/0x1d4 mm/util.c:581 kvmalloc include/linux/slab.h:716 [inline] kvzalloc include/linux/slab.h:724 [inline] alloc_netdev_mqs+0x94/0xc44 net/core/dev.c:10770 gphonet_setup_default drivers/usb/gadget/function/f_phonet.c:706 [inline] phonet_alloc_inst+0xa4/0x170 drivers/usb/gadget/function/f_phonet.c:640 try_get_usb_function_instance drivers/usb/gadget/functions.c:28 [inline] usb_get_function_instance+0xe8/0x2dc drivers/usb/gadget/functions.c:44 function_make+0x108/0x2f8 drivers/usb/gadget/configfs.c:615 configfs_mkdir+0x3e0/0x884 fs/configfs/dir.c:1360 vfs_mkdir+0x314/0x4d8 fs/namei.c:4114 do_mkdirat+0x1b8/0x3ec fs/namei.c:4139 __do_sys_mkdirat fs/namei.c:4154 [inline] __se_sys_mkdirat fs/namei.c:4152 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4152 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 The buggy address belongs to the object at ffff0000f5330000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 1728 bytes inside of 4096-byte region [ffff0000f5330000, ffff0000f5331000) The buggy address belongs to the physical page: page:000000002ed2529c refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000f5330000 pfn:0x135330 head:000000002ed2529c order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff0000dbed5501 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc000372c008 fffffc000372ae08 ffff0000c0003500 raw: ffff0000f5330000 0000000000040001 00000001ffffffff ffff0000dbed5501 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000f5330580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000f5330600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000f5330680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000f5330700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000f5330780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ------------[ cut here ]------------ Missing register, driver bug WARNING: CPU: 0 PID: 5949 at net/core/xdp.c:136 xdp_rxq_info_unreg_mem_model net/core/xdp.c:136 [inline] WARNING: CPU: 0 PID: 5949 at net/core/xdp.c:136 xdp_rxq_info_unreg+0x94/0x100 net/core/xdp.c:150 Modules linked in: CPU: 0 PID: 5949 Comm: syz.3.413 Tainted: G B syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--) pc : xdp_rxq_info_unreg_mem_model net/core/xdp.c:136 [inline] pc : xdp_rxq_info_unreg+0x94/0x100 net/core/xdp.c:150 lr : xdp_rxq_info_unreg_mem_model net/core/xdp.c:136 [inline] lr : xdp_rxq_info_unreg+0x94/0x100 net/core/xdp.c:150 sp : ffff8000218774c0 x29: ffff8000218774c0 x28: 1fffe0001b278056 x27: ffff0000d2ab40d8 x26: 0000000000000000 x25: 1fffe0001ea660c7 x24: ffff0000f5330638 x23: 1fffe0001d2a6ac1 x22: ffff0000e953560c x21: dfff800000000000 x20: 0000000007d30482 x19: ffff0000e9535600 x18: 1fffe00033e7277e x17: ffff80001537d000 x16: ffff800008043b30 x15: 0000000040000000 x14: 0000000000000001 x13: 1fffe00033e74e70 x12: 0000000000000000 x11: ff00800008048e14 x10: 0000000040000002 x9 : daacc5aaecdfc500 x8 : daacc5aaecdfc500 x7 : ffff800011cec160 x6 : ffff80000825ab4c x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff800021877080 x1 : 0000000000000000 x0 : ffff80000825abe0 Call trace: xdp_rxq_info_unreg_mem_model net/core/xdp.c:136 [inline] xdp_rxq_info_unreg+0x94/0x100 net/core/xdp.c:150 netif_free_rx_queues net/core/dev.c:10021 [inline] free_netdev+0x114/0x428 net/core/dev.c:10887 gphonet_register_netdev drivers/usb/gadget/function/f_phonet.c:729 [inline] pn_bind+0x130/0x9c0 drivers/usb/gadget/function/f_phonet.c:511 usb_add_function+0x234/0x7a8 drivers/usb/gadget/composite.c:337 configfs_composite_bind+0x7e0/0xce4 drivers/usb/gadget/configfs.c:1409 gadget_bind_driver+0x26c/0x684 drivers/usb/gadget/udc/core.c:1651 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x3a0/0xac4 drivers/base/dd.c:638 __driver_probe_device+0x1c8/0x368 drivers/base/dd.c:804 driver_probe_device+0x78/0x324 drivers/base/dd.c:834 __driver_attach+0x3bc/0x614 drivers/base/dd.c:1220 bus_for_each_dev+0x148/0x1d0 drivers/base/bus.c:303 driver_attach+0x50/0x60 drivers/base/dd.c:1237 bus_add_driver+0x2c0/0x518 drivers/base/bus.c:620 driver_register+0x200/0x37c drivers/base/driver.c:246 usb_gadget_register_driver_owner+0xf0/0x25c drivers/usb/gadget/udc/core.c:1730 gadget_dev_desc_UDC_store+0x168/0x268 drivers/usb/gadget/configfs.c:290 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x260/0x338 fs/configfs/file.c:229 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x3c8/0x7c8 fs/read_write.c:584 ksys_write+0x12c/0x228 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 irq event stamp: 877 hardirqs last enabled at (877): [] raw_spin_rq_unlock_irq kernel/sched/sched.h:1374 [inline] hardirqs last enabled at (877): [] finish_lock_switch+0xb0/0x1c8 kernel/sched/core.c:5005 hardirqs last disabled at (876): [] __schedule+0x294/0x1a6c kernel/sched/core.c:6461 softirqs last enabled at (612): [] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (610): [] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]--- Unable to handle kernel paging request at virtual address dfff800000000000 KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] Mem abort info: ESR = 0x0000000096000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 [dfff800000000000] address between user and kernel address ranges Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 5949 Comm: syz.3.413 Tainted: G B W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 pstate: 22400005 (nzCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--) pc : memcmp lib/string.c:772 [inline] pc : bcmp+0x30/0x260 lib/string.c:804 lr : memcmp include/linux/fortify-string.h:549 [inline] lr : dev_addr_check+0x4c/0x1e8 net/core/dev_addr_lists.c:513 sp : ffff800021877430 x29: ffff800021877460 x28: 1fffe0001b278056 x27: ffff0000d2ab40d8 x26: 0000000000000000 x25: 1fffe0001ea660c7 x24: ffff0000f5330638 x23: dfff800000000000 x22: dfff800000000000 x21: 1fffe0001ea66070 x20: 0000000000000000 x19: ffff0000f5330000 x18: 1fffe00033e7277e x17: ffff80001537d000 x16: ffff800011b90510 x15: 0000000040000000 x14: 0000000000000001 x13: 1fffe00033e74e70 x12: 0000000000000000 x11: 0000000000000000 x10: dfff800000000000 x9 : 0000000000000000 x8 : ffff0000f5330c28 x7 : ffff800011cec160 x6 : ffff80000825ab4c x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80000ff29f14 x2 : 0000000000000020 x1 : ffff0000f5330c28 x0 : 0000000000000000 Call trace: memcmp lib/string.c:772 [inline] bcmp+0x30/0x260 lib/string.c:804 memcmp include/linux/fortify-string.h:549 [inline] dev_addr_check+0x4c/0x1e8 net/core/dev_addr_lists.c:513 dev_addr_flush+0x38/0x1e0 net/core/dev_addr_lists.c:533 free_netdev+0x1b0/0x428 net/core/dev.c:10892 gphonet_register_netdev drivers/usb/gadget/function/f_phonet.c:729 [inline] pn_bind+0x130/0x9c0 drivers/usb/gadget/function/f_phonet.c:511 usb_add_function+0x234/0x7a8 drivers/usb/gadget/composite.c:337 configfs_composite_bind+0x7e0/0xce4 drivers/usb/gadget/configfs.c:1409 gadget_bind_driver+0x26c/0x684 drivers/usb/gadget/udc/core.c:1651 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x3a0/0xac4 drivers/base/dd.c:638 __driver_probe_device+0x1c8/0x368 drivers/base/dd.c:804 driver_probe_device+0x78/0x324 drivers/base/dd.c:834 __driver_attach+0x3bc/0x614 drivers/base/dd.c:1220 bus_for_each_dev+0x148/0x1d0 drivers/base/bus.c:303 driver_attach+0x50/0x60 drivers/base/dd.c:1237 bus_add_driver+0x2c0/0x518 drivers/base/bus.c:620 driver_register+0x200/0x37c drivers/base/driver.c:246 usb_gadget_register_driver_owner+0xf0/0x25c drivers/usb/gadget/udc/core.c:1730 gadget_dev_desc_UDC_store+0x168/0x268 drivers/usb/gadget/configfs.c:290 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x260/0x338 fs/configfs/file.c:229 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x3c8/0x7c8 fs/read_write.c:584 ksys_write+0x12c/0x228 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Code: aa0103e8 aa0003e9 d343fd2b 1200092c (38ea696b) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: aa0103e8 mov x8, x1 4: aa0003e9 mov x9, x0 8: d343fd2b lsr x11, x9, #3 c: 1200092c and w12, w9, #0x7 * 10: 38ea696b ldrsb w11, [x11, x10] <-- trapping instruction