| Message ID | 7d33e244-d8b9-4c27-9653-883a13534b01@kili.mountain (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | coresight: Fix signedness bug in tmc_etr_buf_insert_barrier_packet() | expand |
Hi Dan On 21/04/2023 11:42, Dan Carpenter wrote: > This code generates a Smatch warning: > > drivers/hwtracing/coresight/coresight-tmc-etr.c:947 tmc_etr_buf_insert_barrier_packet() > error: uninitialized symbol 'bufp'. > > The problem is that if tmc_sg_table_get_data() returns -EINVAL, then > when we test if "len < CORESIGHT_BARRIER_PKT_SIZE", the negative "len" > value is type promoted to a high unsigned long value which is greater > than CORESIGHT_BARRIER_PKT_SIZE. Fix this bug by adding an explicit > check for error codes. > > Fixes: 75f4e3619fe2 ("coresight: tmc-etr: Add transparent buffer management") > Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> > --- > drivers/hwtracing/coresight/coresight-tmc-etr.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c > index 918d461fcf4a..eaa296ced167 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c > +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c > @@ -942,7 +942,7 @@ tmc_etr_buf_insert_barrier_packet(struct etr_buf *etr_buf, u64 offset) > > len = tmc_etr_buf_get_data(etr_buf, offset, > CORESIGHT_BARRIER_PKT_SIZE, &bufp); > - if (WARN_ON(len < CORESIGHT_BARRIER_PKT_SIZE)) > + if (WARN_ON(len < 0 || len < CORESIGHT_BARRIER_PKT_SIZE)) > return -EINVAL; > coresight_insert_barrier_packet(bufp); > return offset + CORESIGHT_BARRIER_PKT_SIZE; Thanks for the fix, I will send this as fixes at 6.4-rc1, as I have already sent the PULL request for 6.4 Suzuki
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index 918d461fcf4a..eaa296ced167 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -942,7 +942,7 @@ tmc_etr_buf_insert_barrier_packet(struct etr_buf *etr_buf, u64 offset) len = tmc_etr_buf_get_data(etr_buf, offset, CORESIGHT_BARRIER_PKT_SIZE, &bufp); - if (WARN_ON(len < CORESIGHT_BARRIER_PKT_SIZE)) + if (WARN_ON(len < 0 || len < CORESIGHT_BARRIER_PKT_SIZE)) return -EINVAL; coresight_insert_barrier_packet(bufp); return offset + CORESIGHT_BARRIER_PKT_SIZE;
This code generates a Smatch warning: drivers/hwtracing/coresight/coresight-tmc-etr.c:947 tmc_etr_buf_insert_barrier_packet() error: uninitialized symbol 'bufp'. The problem is that if tmc_sg_table_get_data() returns -EINVAL, then when we test if "len < CORESIGHT_BARRIER_PKT_SIZE", the negative "len" value is type promoted to a high unsigned long value which is greater than CORESIGHT_BARRIER_PKT_SIZE. Fix this bug by adding an explicit check for error codes. Fixes: 75f4e3619fe2 ("coresight: tmc-etr: Add transparent buffer management") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> --- drivers/hwtracing/coresight/coresight-tmc-etr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)