This is a note to let you know that I've just added the patch titled tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit() to the 6.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tracing-kprobe-fix-potential-null-ptr-deref-on-trace_array-in-kprobe_event_gen_test_exit.patch and it can be found in the queue-6.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 22ea4ca9631eb137e64e5ab899e9c89cb6670959 Mon Sep 17 00:00:00 2001 From: Shang XiaoJing <shangxiaojing@xxxxxxxxxx> Date: Fri, 18 Nov 2022 10:15:34 +0900 Subject: tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit() From: Shang XiaoJing <shangxiaojing@xxxxxxxxxx> commit 22ea4ca9631eb137e64e5ab899e9c89cb6670959 upstream. When test_gen_kprobe_cmd() failed after kprobe_event_gen_cmd_end(), it will goto delete, which will call kprobe_event_delete() and release the corresponding resource. However, the trace_array in gen_kretprobe_test will point to the invalid resource. Set gen_kretprobe_test to NULL after called kprobe_event_delete() to prevent null-ptr-deref. BUG: kernel NULL pointer dereference, address: 0000000000000070 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 0 PID: 246 Comm: modprobe Tainted: G W 6.1.0-rc1-00174-g9522dc5c87da-dirty #248 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:__ftrace_set_clr_event_nolock+0x53/0x1b0 Code: e8 82 26 fc ff 49 8b 1e c7 44 24 0c ea ff ff ff 49 39 de 0f 84 3c 01 00 00 c7 44 24 18 00 00 00 00 e8 61 26 fc ff 48 8b 6b 10 <44> 8b 65 70 4c 8b 6d 18 41 f7 c4 00 02 00 00 75 2f RSP: 0018:ffffc9000159fe00 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff88810971d268 RCX: 0000000000000000 RDX: ffff8881080be600 RSI: ffffffff811b48ff RDI: ffff88810971d058 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffffc9000159fe58 R11: 0000000000000001 R12: ffffffffa0001064 R13: ffffffffa000106c R14: ffff88810971d238 R15: 0000000000000000 FS: 00007f89eeff6540(0000) GS:ffff88813b600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000070 CR3: 000000010599e004 CR4: 0000000000330ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __ftrace_set_clr_event+0x3e/0x60 trace_array_set_clr_event+0x35/0x50 ? 0xffffffffa0000000 kprobe_event_gen_test_exit+0xcd/0x10b [kprobe_event_gen_test] __x64_sys_delete_module+0x206/0x380 ? lockdep_hardirqs_on_prepare+0xd8/0x190 ? syscall_enter_from_user_mode+0x1c/0x50 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f89eeb061b7 Link: https://lore.kernel.org/all/20221108015130.28326-3-shangxiaojing@xxxxxxxxxx/ Fixes: 64836248dda2 ("tracing: Add kprobe event command generation test module") Signed-off-by: Shang XiaoJing <shangxiaojing@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/trace/kprobe_event_gen_test.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/kernel/trace/kprobe_event_gen_test.c +++ b/kernel/trace/kprobe_event_gen_test.c @@ -143,6 +143,8 @@ static int __init test_gen_kprobe_cmd(vo kfree(buf); return ret; delete: + if (trace_event_file_is_valid(gen_kprobe_test)) + gen_kprobe_test = NULL; /* We got an error after creating the event, delete it */ ret = kprobe_event_delete("gen_kprobe_test"); goto out; @@ -206,6 +208,8 @@ static int __init test_gen_kretprobe_cmd kfree(buf); return ret; delete: + if (trace_event_file_is_valid(gen_kretprobe_test)) + gen_kretprobe_test = NULL; /* We got an error after creating the event, delete it */ ret = kprobe_event_delete("gen_kretprobe_test"); goto out; Patches currently in stable-queue which might be from shangxiaojing@xxxxxxxxxx are queue-6.0/tracing-kprobe-fix-potential-null-ptr-deref-on-trace_array-in-kprobe_event_gen_test_exit.patch queue-6.0/drm-fix-potential-null-ptr-deref-in-drm_vblank_destr.patch queue-6.0/tracing-kprobe-fix-potential-null-ptr-deref-on-trace_event_file-in-kprobe_event_gen_test_exit.patch queue-6.0/drm-drv-fix-potential-memory-leak-in-drm_dev_init.patch queue-6.0/net-microchip-sparx5-fix-potential-null-ptr-deref-in.patch queue-6.0/tracing-fix-memory-leak-in-test_gen_synth_cmd-and-test_empty_synth_event.patch queue-6.0/net-lan966x-fix-potential-null-ptr-deref-in-lan966x_.patch queue-6.0/tracing-fix-wild-memory-access-in-register_synth_event.patch