From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>,
Roman Gushchin <guro@fb.com>, Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Sasha Levin <sashal@kernel.org>,
netdev@vger.kernel.org, bpf@vger.kernel.org
Subject: [PATCH AUTOSEL 5.0 23/34] bpf: Fix preempt_enable_no_resched() abuse
Date: Thu, 16 May 2019 07:39:20 -0400 [thread overview]
Message-ID: <20190516113932.8348-23-sashal@kernel.org> (raw)
In-Reply-To: <20190516113932.8348-1-sashal@kernel.org>
From: Peter Zijlstra <peterz@infradead.org>
[ Upstream commit 0edd6b64d1939e9e9168ff27947995bb7751db5d ]
Unless the very next line is schedule(), or implies it, one must not use
preempt_enable_no_resched(). It can cause a preemption to go missing and
thereby cause arbitrary delays, breaking the PREEMPT=y invariant.
Cc: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/linux/bpf.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index e734f163bd0b9..1fbd7672e4b37 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -455,7 +455,7 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
} \
_out: \
rcu_read_unlock(); \
- preempt_enable_no_resched(); \
+ preempt_enable(); \
_ret; \
})
--
2.20.1
next prev parent reply other threads:[~2019-05-16 11:40 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-16 11:38 [PATCH AUTOSEL 5.0 01/34] xfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink Sasha Levin
2019-05-16 11:38 ` [PATCH AUTOSEL 5.0 02/34] xfrm: Reset secpath in xfrm failure Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 03/34] xfrm6_tunnel: Fix potential panic when unloading xfrm6_tunnel module Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 04/34] vti4: ipip tunnel deregistration fixes Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 05/34] xfrm: clean up xfrm protocol checks Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 06/34] esp4: add length check for UDP encapsulation Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 07/34] xfrm: Honor original L3 slave device in xfrmi policy lookup Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 08/34] xfrm4: Fix uninitialized memory read in _decode_session4 Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 09/34] ARC: PAE40: don't panic and instead turn off hw ioc Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 10/34] clk: sunxi-ng: nkmp: Avoid GENMASK(-1, 0) Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 11/34] KVM: PPC: Book3S HV: Perserve PSSCR FAKE_SUSPEND bit on guest exit Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 12/34] KVM: PPC: Book3S: Protect memslots while validating user address Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 13/34] power: supply: cpcap-battery: Fix division by zero Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 14/34] securityfs: fix use-after-free on symlink traversal Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 15/34] apparmorfs: " Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 16/34] PCI: Fix issue with "pci=disable_acs_redir" parameter being ignored Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 17/34] x86: kvm: hyper-v: deal with buggy TLB flush requests from WS2012 Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 18/34] mac80211: Fix kernel panic due to use of txq after free Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 19/34] net: ieee802154: fix missing checks for regmap_update_bits Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 20/34] KVM: arm/arm64: Ensure vcpu target is unset on reset failure Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 21/34] power: supply: sysfs: prevent endless uevent loop with CONFIG_POWER_SUPPLY_DEBUG Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 22/34] tools: bpftool: fix infinite loop in map create Sasha Levin
2019-05-16 11:39 ` Sasha Levin [this message]
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 24/34] qmi_wwan: new Wistron, ZTE and D-Link devices Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 25/34] iwlwifi: mvm: check for length correctness in iwl_mvm_create_skb() Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 26/34] sched/cpufreq: Fix kobject memleak Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 27/34] x86/mm/mem_encrypt: Disable all instrumentation for early SME setup Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 28/34] KVM: fix KVM_CLEAR_DIRTY_LOG for memory slots of unaligned size Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 29/34] KVM: selftests: make hyperv_cpuid test pass on AMD Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 30/34] ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 31/34] i2c: designware: ratelimit 'transfer when suspended' errors Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 32/34] perf bench numa: Add define for RUSAGE_THREAD if not present Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 33/34] perf cs-etm: Always allocate memory for cs_etm_queue::prev_packet Sasha Levin
2019-05-16 11:39 ` [PATCH AUTOSEL 5.0 34/34] perf/x86/intel: Fix race in intel_pmu_disable_event() Sasha Levin
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