The following commit has been merged into the perf/urgent branch of tip: Commit-ID: 0b3a8738b76fe2087f7bc2bd59f4c78504c79180 Gitweb: https://git.kernel.org/tip/0b3a8738b76fe2087f7bc2bd59f4c78504c79180 Author: Colin Ian King <colin.king@xxxxxxxxxxxxx> AuthorDate: Tue, 06 Jul 2021 12:45:53 +01:00 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitterDate: Thu, 26 Aug 2021 08:58:02 +02:00 perf/x86/intel/uncore: Fix integer overflow on 23 bit left shift of a u32 The u32 variable pci_dword is being masked with 0x1fffffff and then left shifted 23 places. The shift is a u32 operation,so a value of 0x200 or more in pci_dword will overflow the u32 and only the bottow 32 bits are assigned to addr. I don't believe this was the original intent. Fix this by casting pci_dword to a resource_size_t to ensure no overflow occurs. Note that the mask and 12 bit left shift operation does not need this because the mask SNR_IMC_MMIO_MEM0_MASK and shift is always a 32 bit value. Fixes: ee49532b38dd ("perf/x86/intel/uncore: Add IMC uncore support for Snow Ridge") Addresses-Coverity: ("Unintentional integer overflow") Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210706114553.28249-1-colin.king@xxxxxxxxxxxxx --- arch/x86/events/intel/uncore_snbep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c index 609c24a..c682b09 100644 --- a/arch/x86/events/intel/uncore_snbep.c +++ b/arch/x86/events/intel/uncore_snbep.c @@ -4811,7 +4811,7 @@ static void __snr_uncore_mmio_init_box(struct intel_uncore_box *box, return; pci_read_config_dword(pdev, SNR_IMC_MMIO_BASE_OFFSET, &pci_dword); - addr = (pci_dword & SNR_IMC_MMIO_BASE_MASK) << 23; + addr = ((resource_size_t)pci_dword & SNR_IMC_MMIO_BASE_MASK) << 23; pci_read_config_dword(pdev, mem_offset, &pci_dword); addr |= (pci_dword & SNR_IMC_MMIO_MEM0_MASK) << 12;
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