CVE-2022-49796

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit()<br /> <br /> When test_gen_kprobe_cmd() failed after kprobe_event_gen_cmd_end(), it<br /> will goto delete, which will call kprobe_event_delete() and release the<br /> corresponding resource. However, the trace_array in gen_kretprobe_test<br /> will point to the invalid resource. Set gen_kretprobe_test to NULL<br /> after called kprobe_event_delete() to prevent null-ptr-deref.<br /> <br /> BUG: kernel NULL pointer dereference, address: 0000000000000070<br /> PGD 0 P4D 0<br /> Oops: 0000 [#1] SMP PTI<br /> CPU: 0 PID: 246 Comm: modprobe Tainted: G W<br /> 6.1.0-rc1-00174-g9522dc5c87da-dirty #248<br /> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS<br /> rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014<br /> RIP: 0010:__ftrace_set_clr_event_nolock+0x53/0x1b0<br /> Code: e8 82 26 fc ff 49 8b 1e c7 44 24 0c ea ff ff ff 49 39 de 0f 84 3c<br /> 01 00 00 c7 44 24 18 00 00 00 00 e8 61 26 fc ff 48 8b 6b 10 8b 65<br /> 70 4c 8b 6d 18 41 f7 c4 00 02 00 00 75 2f<br /> RSP: 0018:ffffc9000159fe00 EFLAGS: 00010293<br /> RAX: 0000000000000000 RBX: ffff88810971d268 RCX: 0000000000000000<br /> RDX: ffff8881080be600 RSI: ffffffff811b48ff RDI: ffff88810971d058<br /> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001<br /> R10: ffffc9000159fe58 R11: 0000000000000001 R12: ffffffffa0001064<br /> R13: ffffffffa000106c R14: ffff88810971d238 R15: 0000000000000000<br /> FS: 00007f89eeff6540(0000) GS:ffff88813b600000(0000)<br /> knlGS:0000000000000000<br /> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> CR2: 0000000000000070 CR3: 000000010599e004 CR4: 0000000000330ef0<br /> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000<br /> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400<br /> Call Trace:<br /> <br /> __ftrace_set_clr_event+0x3e/0x60<br /> trace_array_set_clr_event+0x35/0x50<br /> ? 0xffffffffa0000000<br /> kprobe_event_gen_test_exit+0xcd/0x10b [kprobe_event_gen_test]<br /> __x64_sys_delete_module+0x206/0x380<br /> ? lockdep_hardirqs_on_prepare+0xd8/0x190<br /> ? syscall_enter_from_user_mode+0x1c/0x50<br /> do_syscall_64+0x3f/0x90<br /> entry_SYSCALL_64_after_hwframe+0x63/0xcd<br /> RIP: 0033:0x7f89eeb061b7