diff mbox series

lib/librte_power: fix using variables before validity check

Message ID 1619355594-15223-1-git-send-email-humin29@huawei.com (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers
Series lib/librte_power: fix using variables before validity check |

Checks

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ci/checkpatch success coding style OK
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-intel-Performance success Performance Testing PASS
ci/Intel-compilation success Compilation OK
ci/iol-abi-testing success Testing PASS
ci/iol-testing success Testing PASS
ci/github-robot success github build: passed
ci/intel-Testing success Testing PASS
ci/iol-mellanox-Performance success Performance Testing PASS

Commit Message

humin (Q) April 25, 2021, 12:59 p.m. UTC 
  From: HongBo Zheng <zhenghongbo3@huawei.com>

In function power_guest_channel_read_msg, 'lcore_id' is used before
validity check, which may cause buffer 'global_fds' accessed by index
'lcore_id' overflow.

This patch moves the validity check of 'lcore_id' before the 'lcore_id'
being used for the first time.

Fixes: 9dc843eb273b ("power: extend guest channel API for reading")
Cc: stable@dpdk.org

Signed-off-by: HongBo Zheng <zhenghongbo3@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
---
 lib/power/guest_channel.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

Comments

Pattan, Reshma April 28, 2021, 3:13 p.m. UTC | #1 
> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Min Hu (Connor)
> 
> +	if (lcore_id >= RTE_MAX_LCORE) {
> +		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range
> 0...%d\n",
> +				lcore_id, RTE_MAX_LCORE-1);
> +		return -1;
> +	}
> +

This looks good.

>  	fds.fd = global_fds[lcore_id];
>  	fds.events = POLLIN;
> 
<snip>

>  	if (global_fds[lcore_id] < 0) {
>  		RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not
> connected\n");


Another suggestion if you would like to improve the code, is below,
You can move "global_fds[lcore_id]"  check to immediate after  the line  "fds.fd = global_fds[lcore_id]; "

Reviewed-by: Reshma Pattan <reshma.pattan@intel.com>
humin (Q) April 29, 2021, 12:43 a.m. UTC | #2 
在 2021/4/28 23:13, Pattan, Reshma 写道:
> 
> 
>> -----Original Message-----
>> From: dev <dev-bounces@dpdk.org> On Behalf Of Min Hu (Connor)
>>
>> +	if (lcore_id >= RTE_MAX_LCORE) {
>> +		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range
>> 0...%d\n",
>> +				lcore_id, RTE_MAX_LCORE-1);
>> +		return -1;
>> +	}
>> +
> 
> This looks good.
> 
>>   	fds.fd = global_fds[lcore_id];
>>   	fds.events = POLLIN;
>>
> <snip>
> 
>>   	if (global_fds[lcore_id] < 0) {
>>   		RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not
>> connected\n");
> 
> 
> Another suggestion if you would like to improve the code, is below,
> You can move "global_fds[lcore_id]"  check to immediate after  the line  "fds.fd = global_fds[lcore_id]; "
Hi, thanks Pattan.
But I think "global_fds[lcore_id]"  check may move before the line 
"fds.fd = global_fds[lcore_id];
If it failed, "fds.fd = global_fds[lcore_id];" should not be performed.
What's your opinion?

> 
> Reviewed-by: Reshma Pattan <reshma.pattan@intel.com>
> 
> .
>
Thomas Monjalon May 11, 2021, 1:25 p.m. UTC | #3 
Any comment please?

29/04/2021 02:43, Min Hu (Connor):
> 
> 在 2021/4/28 23:13, Pattan, Reshma 写道:
> > 
> > 
> >> -----Original Message-----
> >> From: dev <dev-bounces@dpdk.org> On Behalf Of Min Hu (Connor)
> >>
> >> +	if (lcore_id >= RTE_MAX_LCORE) {
> >> +		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range
> >> 0...%d\n",
> >> +				lcore_id, RTE_MAX_LCORE-1);
> >> +		return -1;
> >> +	}
> >> +
> > 
> > This looks good.
> > 
> >>   	fds.fd = global_fds[lcore_id];
> >>   	fds.events = POLLIN;
> >>
> > <snip>
> > 
> >>   	if (global_fds[lcore_id] < 0) {
> >>   		RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not
> >> connected\n");
> > 
> > 
> > Another suggestion if you would like to improve the code, is below,
> > You can move "global_fds[lcore_id]"  check to immediate after  the line  "fds.fd = global_fds[lcore_id]; "
> Hi, thanks Pattan.
> But I think "global_fds[lcore_id]"  check may move before the line 
> "fds.fd = global_fds[lcore_id];
> If it failed, "fds.fd = global_fds[lcore_id];" should not be performed.
> What's your opinion?
> 
> > 
> > Reviewed-by: Reshma Pattan <reshma.pattan@intel.com>
Pattan, Reshma May 11, 2021, 1:34 p.m. UTC | #4 
> -----Original Message-----
> From: Min Hu (Connor) <humin29@huawei.com>
> > Another suggestion if you would like to improve the code, is below,
> > You can move "global_fds[lcore_id]"  check to immediate after  the line
> "fds.fd = global_fds[lcore_id]; "
> Hi, thanks Pattan.
> But I think "global_fds[lcore_id]"  check may move before the line
> "fds.fd = global_fds[lcore_id];
> If it failed, "fds.fd = global_fds[lcore_id];" should not be performed.
> What's your opinion?
> 

That is correct.  You can do that change.
diff mbox series

Patch

diff --git a/lib/power/guest_channel.c b/lib/power/guest_channel.c
index 2f7507a..d3de3f1 100644
--- a/lib/power/guest_channel.c
+++ b/lib/power/guest_channel.c
@@ -166,6 +166,12 @@  int power_guest_channel_read_msg(void *pkt,
 	if (pkt_len == 0 || pkt == NULL)
 		return -1;
 
+	if (lcore_id >= RTE_MAX_LCORE) {
+		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
+				lcore_id, RTE_MAX_LCORE-1);
+		return -1;
+	}
+
 	fds.fd = global_fds[lcore_id];
 	fds.events = POLLIN;
 
@@ -179,12 +185,6 @@  int power_guest_channel_read_msg(void *pkt,
 		return -1;
 	}
 
-	if (lcore_id >= RTE_MAX_LCORE) {
-		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
-				lcore_id, RTE_MAX_LCORE-1);
-		return -1;
-	}
-
 	if (global_fds[lcore_id] < 0) {
 		RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not connected\n");
 		return -1;