CyberRota Analysis
AI-GeneratedThe vulnerability in the Linux kernel affects the fprobe functionality, specifically in the handling of shadow-stack reservations, which can lead to a NULL pointer dereference. This flaw may result in a general protection fault, potentially causing system instability or crashes. System administrators and developers using affected Linux kernel versions should prioritize addressing this issue to maintain system reliability and security.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: tracing/fprobe: Fix NULL pointer dereference in fprobe_fgraph_entry() fprobe_fgraph_entry() sizes a shadow-stack reservation in one walk of the per-ip fprobe list and fills it in a second walk, both under rcu_read_lock() only. A fprobe registered on an already-live ip can become visible between the two walks, so the fill walk processes an exit_handler the sizing walk did not count and used runs past reserved_words. If the sizing walk counted nothing, fgraph_data is NULL and the first write_fprobe_header() faults: Oops: general protection fault, probably for non-canonical address ... KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:fprobe_fgraph_entry+0xa38/0xf10 kernel/trace/fprobe.c:167 Call Trace: <TASK> function_graph_enter_regs+0x44c/0xa10 kernel/trace/fgraph.c:677 ftrace_graph_func+0xc5/0x140 arch/x86/kernel/ftrace.c:671 __kernel_text_address+0x9/0x40 kernel/extable.c:78 arch_stack_walk+0x117/0x170 arch/x86/kernel/stacktrace.c:26 kmem_cache_free+0x188/0x580 mm/slub.c:6378 tcp_data_queue+0x18d/0x6550 net/ipv4/tcp_input.c:5590 [...] </TASK> The list cannot be frozen across the two walks, so skip a node that does not fit the reservation and count it as missed.