8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 0000000e when read [0000000e] *pgd=85e2f003, *pmd=e009f003 Internal error: Oops: 205 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 13112 Comm: syz.1.1210 Not tainted 6.15.0-rc6-syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at io_ring_buffer_select io_uring/kbuf.c:163 [inline] PC is at io_buffer_select+0x50/0x18c io_uring/kbuf.c:207 LR is at rcu_read_unlock include/linux/rcupdate.h:873 [inline] LR is at xa_load+0x68/0xa4 lib/xarray.c:1621 pc : [<80889b64>] lr : [<81a4c654>] psr: 20000013 sp : dfa89de8 ip : dfa89da8 fp : dfa89e04 r10: 834ad180 r9 : 00000000 r8 : 80000001 r7 : dfa89e20 r6 : 00000000 r5 : 8540f100 r4 : 85ae0000 r3 : 00000001 r2 : 00000000 r1 : 85106480 r0 : 00000000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84c070c0 DAC: fffffffd Register r0 information: NULL pointer Register r1 information: slab kmalloc-64 start 85106480 pointer offset 0 size 64 Register r2 information: NULL pointer Register r3 information: non-paged memory Register r4 information: slab io_kiocb start 85ae0000 pointer offset 0 size 192 Register r5 information: slab kmalloc-2k start 8540f000 pointer offset 256 size 2048 Register r6 information: NULL pointer Register r7 information: 2-page vmalloc region starting at 0xdfa88000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Register r8 information: non-slab/vmalloc memory Register r9 information: NULL pointer Register r10 information: slab sock_inode_cache start 834ad180 pointer offset 0 size 576 Register r11 information: 2-page vmalloc region starting at 0xdfa88000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Register r12 information: 2-page vmalloc region starting at 0xdfa88000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Process syz.1.1210 (pid: 13112, stack limit = 0xdfa88000) Stack: (0xdfa89de8 to 0xdfa8a000) 9de0: 85ae0000 850e9f00 00000000 00000040 dfa89e54 dfa89e08 9e00: 80892e90 80889b20 dfa89e78 b5003500 b5403587 00000001 0100000a 00000000 9e20: 00000000 6e524cc4 dfa89e54 85ae0000 81cf0bd4 00000000 00000000 00000000 9e40: 80000001 84f4d400 dfa89e7c dfa89e58 80882314 80892c6c 85ae0000 80000001 9e60: 0000000a 81cf0b5c 84ddb600 00000000 dfa89ebc dfa89e80 80886de4 808822d4 9e80: 00000000 00000000 00000000 81cf0bd4 00000000 8540f000 85ae006c 85ae0000 9ea0: 85488000 00000000 00000000 84f4d400 dfa89f14 dfa89ec0 808878fc 80886da8 9ec0: 8088e2b8 81a4c5f8 dfa89f24 dfa89ed8 00000001 00000001 81cf0b5c 00000001 9ee0: 8540f000 6e524cc4 84ddb840 00000000 8540f000 000027e2 84ddb840 00000000 9f00: 84f4d400 00000000 dfa89fa4 dfa89f18 808883a4 808876fc ecac8b10 8540f040 9f20: 00000000 00000000 81a503d0 81a502a0 dfa89f54 dfa89f40 8026b438 8029ce24 9f40: dfa89fb0 40000000 dfa89f84 dfa89f58 802229dc 8026b3f4 00000000 8281d05c 9f60: dfa89fb0 0014c490 ecac8b10 80222930 00000000 6e524cc4 dfa89fac 00000000 9f80: 00000000 002e630c 000001aa 8020029c 84f4d400 000001aa 00000000 dfa89fa8 9fa0: 80200060 80888278 00000000 00000000 00000003 000027e2 00000000 00000000 9fc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76b320bc 9fe0: 76b31ec0 76b31eb0 0001939c 00131f30 60000010 00000003 00000000 00000000 Call trace: [<80889b14>] (io_buffer_select) from [<80892e90>] (io_recvmsg+0x230/0x420 io_uring/net.c:988) r7:00000040 r6:00000000 r5:850e9f00 r4:85ae0000 [<80892c60>] (io_recvmsg) from [<80882314>] (__io_issue_sqe+0x4c/0x1c0 io_uring/io_uring.c:1734) r10:84f4d400 r9:80000001 r8:00000000 r7:00000000 r6:00000000 r5:81cf0bd4 r4:85ae0000 [<808822c8>] (__io_issue_sqe) from [<80886de4>] (io_issue_sqe+0x48/0x59c io_uring/io_uring.c:1757) r9:00000000 r8:84ddb600 r7:81cf0b5c r6:0000000a r5:80000001 r4:85ae0000 [<80886d9c>] (io_issue_sqe) from [<808878fc>] (io_queue_sqe io_uring/io_uring.c:1963 [inline]) [<80886d9c>] (io_issue_sqe) from [<808878fc>] (io_submit_sqe io_uring/io_uring.c:2219 [inline]) [<80886d9c>] (io_issue_sqe) from [<808878fc>] (io_submit_sqes+0x20c/0x938 io_uring/io_uring.c:2336) r10:84f4d400 r9:00000000 r8:00000000 r7:85488000 r6:85ae0000 r5:85ae006c r4:8540f000 [<808876f0>] (io_submit_sqes) from [<808883a4>] (__do_sys_io_uring_enter io_uring/io_uring.c:3396 [inline]) [<808876f0>] (io_submit_sqes) from [<808883a4>] (sys_io_uring_enter+0x138/0x780 io_uring/io_uring.c:3330) r10:00000000 r9:84f4d400 r8:00000000 r7:84ddb840 r6:000027e2 r5:8540f000 r4:00000000 [<8088826c>] (sys_io_uring_enter) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa89fa8 to 0xdfa89ff0) 9fa0: 00000000 00000000 00000003 000027e2 00000000 00000000 9fc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76b320bc 9fe0: 76b31ec0 76b31eb0 0001939c 00131f30 r10:000001aa r9:84f4d400 r8:8020029c r7:000001aa r6:002e630c r5:00000000 r4:00000000 Code: e3130001 0a00002f e5910000 e1d120be (e1d030be) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e3130001 tst r3, #1 4: 0a00002f beq 0xc8 8: e5910000 ldr r0, [r1] c: e1d120be ldrh r2, [r1, #14] * 10: e1d030be ldrh r3, [r0, #14] <-- trapping instruction