Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: uprobes: Fix NULL pointer dereference in hprobe_expire() Forking a task that has a pending uretprobe can oops the kernel with a NULL pointer dereference in the clone() path: BUG: kernel NULL pointer dereference, address: 0000000000000018 Oops: 0002 [#1] SMP NOPTI RIP: 0010:hprobe_expire CR2: 0000000000000018 Call Trace: uprobe_copy_process copy_process kernel_clone __x64_sys_clone do_syscall_64 entry_SYSCALL_64_after_hwframe This was found on real hosts on Meta fleet. I've got the impression that this is what is happening: CPU 1 CPU 2 (traced task) ----- ------------------- hit uprobe, prepare_uretprobe(): hprobe LEASED, refcount >= 1 uprobe_unregister() put_uprobe(): refcount -> 0 fork() -> dup_utask() hprobe_expire(hprobe, true) try_get_uprobe() -> NULL get_uprobe(NULL) <-- Oops Only take the extra reference when the uprobe is non-NULL; a NULL means it is gone and is the correct value to return.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected dd1a7567784e2b1f80258be04f57bcfa82c997eb before 3bd35a5e272a1b7a3fb43acad9bdc599281b13fa; affected dd1a7567784e2b1f80258be04f57bcfa82c997eb before 06c275a6c0a953ef1d763d11a6891fcc69ae2ac0; affected dd1a7567784e2b1f80258be04f57bcfa82c997eb before cc679d7a6303e84d769f2afcde1fc51c51f127cd |
| Linux / Linux | affected 6.13; unaffected 0 before 6.13; unaffected 6.18.44 through 6.18.*; unaffected 7.1.8 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.