From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Nick Desaulniers <ndesaulniers@google.com>,
Sudip Mukherjee <sudipm.mukherjee@gmail.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Nathan Chancellor <nathan@kernel.org>,
Sasha Levin <sashal@kernel.org>,
akpm@linux-foundation.org, elver@google.com, jpoimboe@kernel.org,
keescook@chromium.org, llvm@lists.linux.dev
Subject: [PATCH AUTOSEL 5.15 42/42] ubsan: disable UBSAN_DIV_ZERO for clang
Date: Tue, 19 Jul 2022 21:13:50 -0400 [thread overview]
Message-ID: <20220720011350.1024134-42-sashal@kernel.org> (raw)
In-Reply-To: <20220720011350.1024134-1-sashal@kernel.org>
From: Nick Desaulniers <ndesaulniers@google.com>
[ Upstream commit e5d523f1ae8f2cef01f8e071aeee432654166708 ]
Building with UBSAN_DIV_ZERO with clang produces numerous fallthrough
warnings from objtool.
In the case of uncheck division, UBSAN_DIV_ZERO may introduce new
control flow to check for division by zero.
Because the result of the division is undefined, LLVM may optimize the
control flow such that after the call to __ubsan_handle_divrem_overflow
doesn't matter. If panic_on_warn was set,
__ubsan_handle_divrem_overflow would panic.
The problem is is that panic_on_warn is run time configurable. If it's
disabled, then we cannot guarantee that we will be able to recover
safely. Disable this config for clang until we can come up with a
solution in LLVM.
Link: https://github.com/ClangBuiltLinux/linux/issues/1657
Link: https://github.com/llvm/llvm-project/issues/56289
Link: https://lore.kernel.org/lkml/CAHk-=wj1qhf7y3VNACEexyp5EbkNpdcu_542k-xZpzmYLOjiCg@mail.gmail.com/
Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
lib/Kconfig.ubsan | 3 +++
1 file changed, 3 insertions(+)
diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan
index 236c5cefc4cc..641ac2d0477c 100644
--- a/lib/Kconfig.ubsan
+++ b/lib/Kconfig.ubsan
@@ -96,6 +96,9 @@ config UBSAN_SHIFT
config UBSAN_DIV_ZERO
bool "Perform checking for integer divide-by-zero"
depends on $(cc-option,-fsanitize=integer-divide-by-zero)
+ # https://github.com/ClangBuiltLinux/linux/issues/1657
+ # https://github.com/llvm/llvm-project/issues/56289
+ depends on !CC_IS_CLANG
help
This option enables -fsanitize=integer-divide-by-zero which checks
for integer division by zero. This is effectively redundant with the
--
2.35.1
prev parent reply other threads:[~2022-07-20 1:22 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-20 1:13 [PATCH AUTOSEL 5.15 01/42] Revert "evm: Fix memleak in init_desc" Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 02/42] ARM: rockchip: Add missing of_node_put() in rockchip_suspend_init() Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 03/42] x86/kvm/vmx: Make noinstr clean Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 04/42] x86/cpufeatures: Move RETPOLINE flags to word 11 Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 05/42] x86/retpoline: Swizzle retpoline thunk Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 06/42] x86/vsyscall_emu/64: Don't use RET in vsyscall emulation Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 07/42] x86/sev: Avoid using __x86_return_thunk Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 08/42] objtool: Treat .text.__x86.* as noinstr Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 09/42] x86/bugs: Report AMD retbleed vulnerability Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 10/42] x86/bugs: Add AMD retbleed= boot parameter Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 11/42] x86/bugs: Enable STIBP for JMP2RET Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 12/42] x86/bugs: Keep a per-CPU IA32_SPEC_CTRL value Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 13/42] x86/bugs: Optimize SPEC_CTRL MSR writes Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 14/42] x86/bugs: Split spectre_v2_select_mitigation() and spectre_v2_user_select_mitigation() Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 15/42] x86/bugs: Report Intel retbleed vulnerability Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 16/42] x86/xen: Rename SYS* entry points Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 17/42] x86/bugs: Do IBPB fallback check only once Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 18/42] x86/cpu/amd: Add Spectral Chicken Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 19/42] x86/speculation: Fix RSB filling with CONFIG_RETPOLINE=n Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 20/42] KVM: VMX: Flatten __vmx_vcpu_run() Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 21/42] KVM: VMX: Convert launched argument to flags Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 22/42] KVM: VMX: Prevent guest RSB poisoning attacks with eIBRS Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 23/42] wifi: mac80211: check skb_shared in ieee80211_8023_xmit() Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 24/42] wifi: mac80211: do not wake queues on a vif that is being stopped Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 25/42] wifi: cfg80211: Allow P2P client interface to indicate port authorization Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 26/42] drm: panel-orientation-quirks: Add quirk for the Lenovo Yoga Tablet 2 830 Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 27/42] nilfs2: fix incorrect masking of permission flags for symlinks Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 28/42] ASoC: ti: omap-mcbsp: duplicate sysfs error Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 29/42] ASoC: tlv320adcx140: Fix tx_mask check Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 30/42] ASoC: wm5102: Fix event generation for output compensation Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 31/42] ASoC: wm8998: Fix event generation for input mux Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 32/42] ASoC: cs47l92: Fix event generation for OUT1 demux Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 33/42] ASoC: arizona: Update arizona_aif_cfg_changed to use RX_BCLK_RATE Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 34/42] scsi: target: Fix WRITE_SAME No Data Buffer crash Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 35/42] x86/kexec: Disable RET on kexec Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 36/42] platform/x86: asus-wmi: Add key mappings Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 37/42] platform/x86: intel_atomisp2_led: Also turn off the always-on camera LED on the Asus T100TAF Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 38/42] scsi: ufs: core: Fix missing clk change notification on host reset Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 39/42] scsi: pm80xx: Fix 'Unknown' max/min linkrate Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 40/42] scsi: pm80xx: Set stopped phy's linkrate to Disabled Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 41/42] KVM: nVMX: Always enable TSC scaling for L2 when it was enabled for L1 Sasha Levin
2022-07-20 1:13 ` Sasha Levin [this message]
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