* [PATCH] ax25: unsigned cannot be less than 0 in ax25_ctl_ioctl()
@ 2009-10-10 21:22 Roel Kluin
[not found] ` <4AD34D3C.1060206@bfs.de>
0 siblings, 1 reply; 7+ messages in thread
From: Roel Kluin @ 2009-10-10 21:22 UTC (permalink / raw)
To: Joerg Reuter, linux-hams, Andrew Morton, netdev
struct ax25_ctl_struct member `arg' is unsigned and cannot be less
than 0.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
---
If the ax25_ctl.arg limit is known to be lower, please suggest
other values.
diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
index f454607..0d99704 100644
--- a/net/ax25/af_ax25.c
+++ b/net/ax25/af_ax25.c
@@ -398,14 +398,14 @@ static int ax25_ctl_ioctl(const unsigned int cmd, void __user *arg)
break;
case AX25_T1:
- if (ax25_ctl.arg < 1)
+ if (ax25_ctl.arg < 1 || ax25_ctl.arg * HZ > ULONG_MAX)
goto einval_put;
ax25->rtt = (ax25_ctl.arg * HZ) / 2;
ax25->t1 = ax25_ctl.arg * HZ;
break;
case AX25_T2:
- if (ax25_ctl.arg < 1)
+ if (ax25_ctl.arg < 1 || ax25_ctl.arg * HZ > ULONG_MAX)
goto einval_put;
ax25->t2 = ax25_ctl.arg * HZ;
break;
@@ -418,13 +418,13 @@ static int ax25_ctl_ioctl(const unsigned int cmd, void __user *arg)
break;
case AX25_T3:
- if (ax25_ctl.arg < 0)
+ if (ax25_ctl.arg * HZ > ULONG_MAX)
goto einval_put;
ax25->t3 = ax25_ctl.arg * HZ;
break;
case AX25_IDLE:
- if (ax25_ctl.arg < 0)
+ if (ax25_ctl.arg * 60 * HZ > ULONG_MAX)
goto einval_put;
ax25->idle = ax25_ctl.arg * 60 * HZ;
break;
^ permalink raw reply related [flat|nested] 7+ messages in thread[parent not found: <4AD34D3C.1060206@bfs.de>]
* Re: [PATCH] ax25: unsigned cannot be less than 0 in ax25_ctl_ioctl() [not found] ` <4AD34D3C.1060206@bfs.de> @ 2009-10-12 19:02 ` Roel Kluin 2009-10-12 21:58 ` Kevin Dawson 0 siblings, 1 reply; 7+ messages in thread From: Roel Kluin @ 2009-10-12 19:02 UTC (permalink / raw) To: wharms; +Cc: linux-hams, netdev, Joerg Reuter, Andrew Morton struct ax25_ctl_struct member `arg' is unsigned and cannot be less than 0. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> --- >> If the ax25_ctl.arg limit is known to be lower, please suggest >> other values. > what is about something like: > > tmp_arg=ax25_ctl.arg * HZ; > > if (arg == 0 || arg > ULONG_MAX ) > goto einval_put; > > re, > wh I'm not sure, I think this would only work if we made `arg' an unsigned long long. How about this? diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index f454607..20ff0f3 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -369,6 +369,9 @@ static int ax25_ctl_ioctl(const unsigned int cmd, void __user *arg) if (ax25_ctl.digi_count > AX25_MAX_DIGIS) return -EINVAL; + if (ax25_ctl.arg * HZ > ULONG_MAX && ax25_ctl.cmd != AX25_KILL) + return -EINVAL; + digi.ndigi = ax25_ctl.digi_count; for (k = 0; k < digi.ndigi; k++) digi.calls[k] = ax25_ctl.digi_addr[k]; @@ -418,14 +421,10 @@ static int ax25_ctl_ioctl(const unsigned int cmd, void __user *arg) break; case AX25_T3: - if (ax25_ctl.arg < 0) - goto einval_put; ax25->t3 = ax25_ctl.arg * HZ; break; case AX25_IDLE: - if (ax25_ctl.arg < 0) - goto einval_put; ax25->idle = ax25_ctl.arg * 60 * HZ; break; ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] ax25: unsigned cannot be less than 0 in ax25_ctl_ioctl() 2009-10-12 19:02 ` Roel Kluin @ 2009-10-12 21:58 ` Kevin Dawson 2009-10-13 9:48 ` walter harms 2009-10-14 15:26 ` Roel Kluin 0 siblings, 2 replies; 7+ messages in thread From: Kevin Dawson @ 2009-10-12 21:58 UTC (permalink / raw) To: Roel Kluin; +Cc: wharms, linux-hams, netdev, Joerg Reuter, Andrew Morton Roel Kluin wrote: >> tmp_arg=ax25_ctl.arg * HZ; >> >> if (arg == 0 || arg > ULONG_MAX ) >> goto einval_put; > > I'm not sure, I think this would only work if we made `arg' an > unsigned long long. That depends on the possible values of ax25_ctl.arg. > + if (ax25_ctl.arg * HZ > ULONG_MAX && ax25_ctl.cmd != AX25_KILL) > + return -EINVAL; Why the need to change arg before comparing it with a constant? Let the compiler do the work: if (ax25_ctl.arg > ULONG_MAX / HZ && ... Kevin ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] ax25: unsigned cannot be less than 0 in ax25_ctl_ioctl() 2009-10-12 21:58 ` Kevin Dawson @ 2009-10-13 9:48 ` walter harms 2009-10-13 21:50 ` Kevin Dawson 2009-10-14 15:26 ` Roel Kluin 1 sibling, 1 reply; 7+ messages in thread From: walter harms @ 2009-10-13 9:48 UTC (permalink / raw) To: Kevin Dawson; +Cc: Roel Kluin, linux-hams, netdev, Joerg Reuter, Andrew Morton Kevin Dawson schrieb: > Roel Kluin wrote: > >>> tmp_arg=ax25_ctl.arg * HZ; >>> >>> if (arg == 0 || arg > ULONG_MAX ) >>> goto einval_put; >> >> I'm not sure, I think this would only work if we made `arg' an >> unsigned long long. > > That depends on the possible values of ax25_ctl.arg. > >> + if (ax25_ctl.arg * HZ > ULONG_MAX && ax25_ctl.cmd != AX25_KILL) >> + return -EINVAL; > > Why the need to change arg before comparing it with a constant? Let the > compiler do the work: > > if (ax25_ctl.arg > ULONG_MAX / HZ && ... > > Kevin > i like this because it prevents a wrap around for stupid ax25_ctl.arg values but will not help when ax25_ctl.arg * HZ is used later. NTL i think HZ does not need to be constant these days but i am not an expert on that area. re, wh ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] ax25: unsigned cannot be less than 0 in ax25_ctl_ioctl() 2009-10-13 9:48 ` walter harms @ 2009-10-13 21:50 ` Kevin Dawson 0 siblings, 0 replies; 7+ messages in thread From: Kevin Dawson @ 2009-10-13 21:50 UTC (permalink / raw) To: wharms; +Cc: linux-hams, netdev, Andrew Morton walter harms wrote: > > Kevin Dawson schrieb: >> >> if (ax25_ctl.arg > ULONG_MAX / HZ && ... > > i like this because it prevents a wrap around for stupid ax25_ctl.arg values but will not help when > ax25_ctl.arg * HZ is used later. NTL i think HZ does not need to be constant these days but i am not an > expert on that area. I don't have a kernel source tree at the moment, so I haven't seen where it's used, but the same size-limiting principle using divisions would apply whether you have constants, variables or function calls. If ax25_ctl.arg * HZ is used later, one should arrange that the thread won't get that far if it has already been deemed an excessive value. Kevin ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] ax25: unsigned cannot be less than 0 in ax25_ctl_ioctl() 2009-10-12 21:58 ` Kevin Dawson 2009-10-13 9:48 ` walter harms @ 2009-10-14 15:26 ` Roel Kluin 2009-10-30 6:06 ` David Miller 1 sibling, 1 reply; 7+ messages in thread From: Roel Kluin @ 2009-10-14 15:26 UTC (permalink / raw) To: Kevin Dawson; +Cc: wharms, linux-hams, netdev, Joerg Reuter, Andrew Morton struct ax25_ctl_struct member `arg' is unsigned and cannot be less than 0. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> --- Op 12-10-09 23:58, Kevin Dawson schreef: >>> tmp_arg=ax25_ctl.arg * HZ; >>> >>> if (arg == 0 || arg > ULONG_MAX ) >>> goto einval_put; >> >> I'm not sure, I think this would only work if we made `arg' an >> unsigned long long. > > That depends on the possible values of ax25_ctl.arg. > >> + if (ax25_ctl.arg * HZ > ULONG_MAX && ax25_ctl.cmd != AX25_KILL) >> + return -EINVAL; > > Why the need to change arg before comparing it with a constant? Let the > compiler do the work: > > if (ax25_ctl.arg > ULONG_MAX / HZ && ... Ok, How about this then? diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index f454607..d923ac4 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -369,6 +369,9 @@ static int ax25_ctl_ioctl(const unsigned int cmd, void __user *arg) if (ax25_ctl.digi_count > AX25_MAX_DIGIS) return -EINVAL; + if (ax25_ctl.arg > ULONG_MAX / HZ && ax25_ctl.cmd != AX25_KILL) + return -EINVAL; + digi.ndigi = ax25_ctl.digi_count; for (k = 0; k < digi.ndigi; k++) digi.calls[k] = ax25_ctl.digi_addr[k]; @@ -418,14 +421,10 @@ static int ax25_ctl_ioctl(const unsigned int cmd, void __user *arg) break; case AX25_T3: - if (ax25_ctl.arg < 0) - goto einval_put; ax25->t3 = ax25_ctl.arg * HZ; break; case AX25_IDLE: - if (ax25_ctl.arg < 0) - goto einval_put; ax25->idle = ax25_ctl.arg * 60 * HZ; break; ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] ax25: unsigned cannot be less than 0 in ax25_ctl_ioctl() 2009-10-14 15:26 ` Roel Kluin @ 2009-10-30 6:06 ` David Miller 0 siblings, 0 replies; 7+ messages in thread From: David Miller @ 2009-10-30 6:06 UTC (permalink / raw) To: roel.kluin; +Cc: kevind, wharms, linux-hams, netdev, jreuter, akpm From: Roel Kluin <roel.kluin@gmail.com> Date: Wed, 14 Oct 2009 17:26:30 +0200 > struct ax25_ctl_struct member `arg' is unsigned and cannot be less > than 0. > > Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Applied to net-next-2.6 ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2009-10-30 6:06 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
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2009-10-10 21:22 [PATCH] ax25: unsigned cannot be less than 0 in ax25_ctl_ioctl() Roel Kluin
[not found] ` <4AD34D3C.1060206@bfs.de>
2009-10-12 19:02 ` Roel Kluin
2009-10-12 21:58 ` Kevin Dawson
2009-10-13 9:48 ` walter harms
2009-10-13 21:50 ` Kevin Dawson
2009-10-14 15:26 ` Roel Kluin
2009-10-30 6:06 ` David Miller
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