From: Akshay Gupta Date: Wed, 16 Jul 2025 11:07:27 +0000 (+0000) Subject: misc: amd-sbi: Address potential integer overflow issue reported in smatch X-Git-Tag: v6.16-rc7~10^2~3 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e108b0a5d339aca9661cd93eb4258b2c661e11e8;p=thirdparty%2Flinux.git misc: amd-sbi: Address potential integer overflow issue reported in smatch Smatch warnings are reported for below commit, Commit bb13a84ed6b7 ("misc: amd-sbi: Add support for CPUID protocol") from Apr 28, 2025 (linux-next), leads to the following Smatch static checker warning: drivers/misc/amd-sbi/rmi-core.c:132 rmi_cpuid_read() warn: bitwise OR is zero '0xffffffff00000000 & 0xffff' drivers/misc/amd-sbi/rmi-core.c:132 rmi_cpuid_read() warn: potential integer overflow from user 'msg->cpu_in_out << 32' drivers/misc/amd-sbi/rmi-core.c:213 rmi_mca_msr_read() warn: bitwise OR is zero '0xffffffff00000000 & 0xffff' drivers/misc/amd-sbi/rmi-core.c:213 rmi_mca_msr_read() warn: potential integer overflow from user 'msg->mcamsr_in_out << 32' CPUID & MCAMSR thread data from input is available at byte 4 & 5, this patch fixes to copy the user data correctly in the argument. Previously, CPUID and MCAMSR data is return only for thread 0. Fixes: bb13a84ed6b7 ("misc: amd-sbi: Add support for CPUID protocol") Fixes: 69b1ba83d21c ("misc: amd-sbi: Add support for read MCA register protocol") Reported-by: Dan Carpenter Closes: https://lore.kernel.org/all/aDVyO8ByVsceybk9@stanley.mountain/ Reviewed-by: Naveen Krishna Chatradhi Signed-off-by: Akshay Gupta Link: https://lore.kernel.org/r/20250716110729.2193725-1-akshay.gupta@amd.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/misc/amd-sbi/rmi-core.c b/drivers/misc/amd-sbi/rmi-core.c index b653a21a909ef..3570f3b269a95 100644 --- a/drivers/misc/amd-sbi/rmi-core.c +++ b/drivers/misc/amd-sbi/rmi-core.c @@ -42,7 +42,6 @@ #define RD_MCA_CMD 0x86 /* CPUID MCAMSR mask & index */ -#define CPUID_MCA_THRD_MASK GENMASK(15, 0) #define CPUID_MCA_THRD_INDEX 32 #define CPUID_MCA_FUNC_MASK GENMASK(31, 0) #define CPUID_EXT_FUNC_INDEX 56 @@ -129,7 +128,7 @@ static int rmi_cpuid_read(struct sbrmi_data *data, goto exit_unlock; } - thread = msg->cpu_in_out << CPUID_MCA_THRD_INDEX & CPUID_MCA_THRD_MASK; + thread = msg->cpu_in_out >> CPUID_MCA_THRD_INDEX; /* Thread > 127, Thread128 CS register, 1'b1 needs to be set to 1 */ if (thread > 127) { @@ -210,7 +209,7 @@ static int rmi_mca_msr_read(struct sbrmi_data *data, goto exit_unlock; } - thread = msg->mcamsr_in_out << CPUID_MCA_THRD_INDEX & CPUID_MCA_THRD_MASK; + thread = msg->mcamsr_in_out >> CPUID_MCA_THRD_INDEX; /* Thread > 127, Thread128 CS register, 1'b1 needs to be set to 1 */ if (thread > 127) {