[v2,2/5] scsi: BusLogic: Avoid unbounded `vsprintf' use
diff mbox series

Message ID alpine.DEB.2.21.2104201939390.44318@angie.orcam.me.uk
State New
Headers show
Series
  • Bring the BusLogic host bus adapter driver up to Y2021
Related show

Commit Message

Maciej W. Rozycki April 20, 2021, 6:01 p.m. UTC
Existing `blogic_msg' invocations do not appear to overrun its internal 
buffer of a fixed length of 100, which would cause stack corruption, but 
it's easy to miss with possible further updates and a fix is cheap in 
performance terms, so limit the output produced into the buffer by using 
`vscnprintf' rather than `vsprintf'.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
---
Changes from v1:

- use `vscnprintf' instead of `vsnprintf' for the correct character count.
---
 drivers/scsi/BusLogic.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

linux-buslogic-vscnprintf.diff

Comments

Khalid Aziz April 22, 2021, 5:30 p.m. UTC | #1
On 4/20/21 12:01 PM, Maciej W. Rozycki wrote:
> Existing `blogic_msg' invocations do not appear to overrun its internal 
> buffer of a fixed length of 100, which would cause stack corruption, but 
> it's easy to miss with possible further updates and a fix is cheap in 
> performance terms, so limit the output produced into the buffer by using 
> `vscnprintf' rather than `vsprintf'.
> 
> Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
> ---
> Changes from v1:
> 
> - use `vscnprintf' instead of `vsnprintf' for the correct character count.
> ---
>  drivers/scsi/BusLogic.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> linux-buslogic-vscnprintf.diff
> Index: linux-macro-ide/drivers/scsi/BusLogic.c
> ===================================================================
> --- linux-macro-ide.orig/drivers/scsi/BusLogic.c
> +++ linux-macro-ide/drivers/scsi/BusLogic.c
> @@ -3588,7 +3588,7 @@ static void blogic_msg(enum blogic_msgle
>  	int len = 0;
>  
>  	va_start(args, adapter);
> -	len = vsprintf(buf, fmt, args);
> +	len = vscnprintf(buf, sizeof(buf), fmt, args);
>  	va_end(args);
>  	if (msglevel == BLOGIC_ANNOUNCE_LEVEL) {
>  		static int msglines = 0;
> 

Acked-by: Khalid Aziz <khalid@gonehiking.org>

Patch
diff mbox series

Index: linux-macro-ide/drivers/scsi/BusLogic.c
===================================================================
--- linux-macro-ide.orig/drivers/scsi/BusLogic.c
+++ linux-macro-ide/drivers/scsi/BusLogic.c
@@ -3588,7 +3588,7 @@  static void blogic_msg(enum blogic_msgle
 	int len = 0;
 
 	va_start(args, adapter);
-	len = vsprintf(buf, fmt, args);
+	len = vscnprintf(buf, sizeof(buf), fmt, args);
 	va_end(args);
 	if (msglevel == BLOGIC_ANNOUNCE_LEVEL) {
 		static int msglines = 0;