Message ID | 20241219232045.51792-1-d.kandybka@gmail.com (mailing list archive) |
---|---|
State | Changes Requested, archived |
Headers | show |
Series | platform/x86/intel: pmc: fix ltr decode in pmc_core_ltr_show() | expand |
On Fri, 20 Dec 2024, Dmitry Kandybka wrote: > In pmc_core_ltr_show(), promote 'val' to 'u64' to avoid possible integer > overflow. Values (10 bit) are multiplied by the scale, the result of > expression is in a range from 1 to 34,326,183,936 which is bigger then > UINT32_MAX. Compile tested only. > > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Signed-off-by: Dmitry Kandybka <d.kandybka@gmail.com> > --- > drivers/platform/x86/intel/pmc/core.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c > index 3e7f99ac8c94..f06ba9636b03 100644 > --- a/drivers/platform/x86/intel/pmc/core.c > +++ b/drivers/platform/x86/intel/pmc/core.c > @@ -660,12 +660,12 @@ static int pmc_core_ltr_show(struct seq_file *s, void *unused) > if (FIELD_GET(LTR_REQ_NONSNOOP, ltr_raw_data)) { > scale = FIELD_GET(LTR_DECODED_SCALE, nonsnoop_ltr); > val = FIELD_GET(LTR_DECODED_VAL, nonsnoop_ltr); > - decoded_non_snoop_ltr = val * convert_ltr_scale(scale); > + decoded_non_snoop_ltr = (u64)val * convert_ltr_scale(scale); > } > if (FIELD_GET(LTR_REQ_SNOOP, ltr_raw_data)) { > scale = FIELD_GET(LTR_DECODED_SCALE, snoop_ltr); > val = FIELD_GET(LTR_DECODED_VAL, snoop_ltr); > - decoded_snoop_ltr = val * convert_ltr_scale(scale); > + decoded_snoop_ltr = (u64)val * convert_ltr_scale(scale); Please change val to u64 instead so casting won't be necessary.
diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c index 3e7f99ac8c94..f06ba9636b03 100644 --- a/drivers/platform/x86/intel/pmc/core.c +++ b/drivers/platform/x86/intel/pmc/core.c @@ -660,12 +660,12 @@ static int pmc_core_ltr_show(struct seq_file *s, void *unused) if (FIELD_GET(LTR_REQ_NONSNOOP, ltr_raw_data)) { scale = FIELD_GET(LTR_DECODED_SCALE, nonsnoop_ltr); val = FIELD_GET(LTR_DECODED_VAL, nonsnoop_ltr); - decoded_non_snoop_ltr = val * convert_ltr_scale(scale); + decoded_non_snoop_ltr = (u64)val * convert_ltr_scale(scale); } if (FIELD_GET(LTR_REQ_SNOOP, ltr_raw_data)) { scale = FIELD_GET(LTR_DECODED_SCALE, snoop_ltr); val = FIELD_GET(LTR_DECODED_VAL, snoop_ltr); - decoded_snoop_ltr = val * convert_ltr_scale(scale); + decoded_snoop_ltr = (u64)val * convert_ltr_scale(scale); } seq_printf(s, "%d\tPMC%d:%-32s\tLTR: RAW: 0x%-16x\tNon-Snoop(ns): %-16llu\tSnoop(ns): %-16llu\tLTR_IGNORE: %d\n",
In pmc_core_ltr_show(), promote 'val' to 'u64' to avoid possible integer overflow. Values (10 bit) are multiplied by the scale, the result of expression is in a range from 1 to 34,326,183,936 which is bigger then UINT32_MAX. Compile tested only. Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Dmitry Kandybka <d.kandybka@gmail.com> --- drivers/platform/x86/intel/pmc/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)