From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from plesk.hostmyservers.fr (plesk.hostmyservers.fr [45.145.164.37]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A762C1A314E; Sun, 12 Oct 2025 13:56:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.145.164.37 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760277416; cv=none; b=PgrTqeUh3vfu60ZYs15lEZn/ShHQf/TOgA3z7FAzVxOtlc9++xLiLHBJPoyjOOXfneAhFTrcJNdW1dp8/cwLluWsJrg9y9Gdwa+c8TSxVRKvxSwi1CCLJDxuDfZ4jZEzU7WFQAA7pUOC1F9+0Yffx6oTxu4KibHTiA6hpweCw90= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760277416; c=relaxed/simple; bh=dfHmpJ3HxLV4gF+y5WmcffGIAAXZtrfoTvfesEZafuE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MhorDEr9dtwPDED9/IG/3I+eZ0a4aMExoh8lbg+ac4JrjPVj/4RLHjHtQojAaWWKgvNQhS5iJ10wSEi1KoUxFMKTIOZwcJH0T7Q3d3MXxIc/SEssLxmHLNOS/JHJStetynhfztBOgu9CKMEr5tPtjQ8e7kCKR19PrKPXXdUPlyo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=arnaud-lcm.com; spf=pass smtp.mailfrom=arnaud-lcm.com; arc=none smtp.client-ip=45.145.164.37 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=arnaud-lcm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arnaud-lcm.com Received: from 7cf34ddaca59.ant.amazon.com (unknown [89.100.17.9]) by plesk.hostmyservers.fr (Postfix) with ESMTPSA id 5E5814018F; Sun, 12 Oct 2025 13:56:50 +0000 (UTC) Authentication-Results: Plesk; spf=pass (sender IP is 89.100.17.9) smtp.mailfrom=contact@arnaud-lcm.com smtp.helo=7cf34ddaca59.ant.amazon.com Received-SPF: pass (Plesk: connection is authenticated) From: Arnaud lecomte To: syzbot+c9b724fbb41cf2538b7b@syzkaller.appspotmail.com Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, contact@arnaud-lcm.com Subject: test Date: Sun, 12 Oct 2025 14:56:49 +0100 Message-ID: <20251012135649.59492-1-contact@arnaud-lcm.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <688809c1.a00a0220.b12ec.00b7.GAE@google.com> References: <688809c1.a00a0220.b12ec.00b7.GAE@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-PPP-Message-ID: <176027741085.28150.16747354518360343128@Plesk> X-PPP-Vhost: arnaud-lcm.com #syz test diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 3615c06b7dfa..c0ee51db8eed 100644 --- a/kernel/bpf/stackmap.c BPF_CALL_3(bpf_get_stackid, struct pt_regs *, regs, struct bpf_map *, map, u64, flags) { - u32 max_depth = map->value_size / stack_map_data_size(map); - u32 skip = flags & BPF_F_SKIP_FIELD_MASK; + u32 elem_size = stack_map_data_size(map); bool user = flags & BPF_F_USER_STACK; struct perf_callchain_entry *trace; bool kernel = !user; + u32 max_depth; if (unlikely(flags & ~(BPF_F_SKIP_FIELD_MASK | BPF_F_USER_STACK | BPF_F_FAST_STACK_CMP | BPF_F_REUSE_STACKID))) return -EINVAL; - max_depth += skip; - if (max_depth > sysctl_perf_event_max_stack) - max_depth = sysctl_perf_event_max_stack; - + max_depth = stack_map_calculate_max_depth(map->value_size, elem_size, flags); trace = get_perf_callchain(regs, 0, kernel, user, max_depth, false, false); @@ -371,15 +391,11 @@ BPF_CALL_3(bpf_get_stackid_pe, struct bpf_perf_event_data_kern *, ctx, return -EFAULT; nr_kernel = count_kernel_ip(trace); + __u64 nr = trace->nr; /* save original */ if (kernel) { - __u64 nr = trace->nr; - trace->nr = nr_kernel; ret = __bpf_get_stackid(map, trace, flags); - - /* restore nr */ - trace->nr = nr; } else { /* user */ u64 skip = flags & BPF_F_SKIP_FIELD_MASK; @@ -390,6 +406,10 @@ BPF_CALL_3(bpf_get_stackid_pe, struct bpf_perf_event_data_kern *, ctx, flags = (flags & ~BPF_F_SKIP_FIELD_MASK) | skip; ret = __bpf_get_stackid(map, trace, flags); } + + /* restore nr */ + trace->nr = nr; + return ret; } @@ -406,7 +426,7 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task, struct perf_callchain_entry *trace_in, void *buf, u32 size, u64 flags, bool may_fault) { - u32 trace_nr, copy_len, elem_size, num_elem, max_depth; + u32 trace_nr, copy_len, elem_size, max_depth; bool user_build_id = flags & BPF_F_USER_BUILD_ID; bool crosstask = task && task != current; u32 skip = flags & BPF_F_SKIP_FIELD_MASK; @@ -438,21 +458,20 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task, goto clear; } - num_elem = size / elem_size; - max_depth = num_elem + skip; - if (sysctl_perf_event_max_stack < max_depth) - max_depth = sysctl_perf_event_max_stack; + max_depth = stack_map_calculate_max_depth(size, elem_size, flags); if (may_fault) rcu_read_lock(); /* need RCU for perf's callchain below */ - if (trace_in) + if (trace_in) { trace = trace_in; - else if (kernel && task) + trace->nr = min_t(u32, trace->nr, max_depth); + } else if (kernel && task) { trace = get_callchain_entry_for_task(task, max_depth); - else + } else { trace = get_perf_callchain(regs, 0, kernel, user, max_depth, crosstask, false); + } if (unlikely(!trace) || trace->nr < skip) { if (may_fault) @@ -461,7 +480,6 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task, } trace_nr = trace->nr - skip; - trace_nr = (trace_nr <= num_elem) ? trace_nr : num_elem; copy_len = trace_nr * elem_size; ips = trace->ip + skip; -- 2.47.3