| Message ID | 20190821070606.GA26957@mwanda (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | dac4f1964a9cbfbf81df8d31caa04ced0d7613b5 |
| Headers | show |
| Series | [1/4] misc: xilinx_sdfec: Fix a couple small information leaks | expand |
Hi Dan, On 21. 08. 19 9:06, Dan Carpenter wrote: > These structs have holes in them so we end up disclosing a few bytes of > uninitialized stack data. > > drivers/misc/xilinx_sdfec.c:305 xsdfec_get_status() warn: check that 'status' doesn't leak information (struct has a hole after 'activity') > drivers/misc/xilinx_sdfec.c:449 xsdfec_get_turbo() warn: check that 'turbo_params' doesn't leak information (struct has a hole after 'scale') Who is generating these warnings? Is this any new GCC or different tool? I see that 3byte padding but never seen these warnings. > We need to zero out the holes with memset(). > > Fixes: 6bd6a690c2e7 ("misc: xilinx_sdfec: Add stats & status ioctls") > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > --- > drivers/misc/xilinx_sdfec.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c > index 912e939dec62..dc1b8b412712 100644 > --- a/drivers/misc/xilinx_sdfec.c > +++ b/drivers/misc/xilinx_sdfec.c > @@ -295,6 +295,7 @@ static int xsdfec_get_status(struct xsdfec_dev *xsdfec, void __user *arg) > struct xsdfec_status status; > int err; > > + memset(&status, 0, sizeof(status)); > spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags); > status.state = xsdfec->state; > xsdfec->state_updated = false; > @@ -440,6 +441,7 @@ static int xsdfec_get_turbo(struct xsdfec_dev *xsdfec, void __user *arg) > if (xsdfec->config.code == XSDFEC_LDPC_CODE) > return -EIO; > > + memset(&turbo_params, 0, sizeof(turbo_params)); > reg_value = xsdfec_regread(xsdfec, XSDFEC_TURBO_ADDR); > > turbo_params.scale = (reg_value & XSDFEC_TURBO_SCALE_MASK) >> > Reviewed-by: Michal Simek <michal.simek@xilinx.com> Thanks, Michal
On Thu, Aug 22, 2019 at 10:14:12AM +0200, Michal Simek wrote: > Hi Dan, > > On 21. 08. 19 9:06, Dan Carpenter wrote: > > These structs have holes in them so we end up disclosing a few bytes of > > uninitialized stack data. > > > > drivers/misc/xilinx_sdfec.c:305 xsdfec_get_status() warn: check that 'status' doesn't leak information (struct has a hole after 'activity') > > drivers/misc/xilinx_sdfec.c:449 xsdfec_get_turbo() warn: check that 'turbo_params' doesn't leak information (struct has a hole after 'scale') > > Who is generating these warnings? Is this any new GCC or different tool? > I see that 3byte padding but never seen these warnings. This is a Smatch check. regards, dan carpenter
On 22. 08. 19 10:28, Dan Carpenter wrote: > On Thu, Aug 22, 2019 at 10:14:12AM +0200, Michal Simek wrote: >> Hi Dan, >> >> On 21. 08. 19 9:06, Dan Carpenter wrote: >>> These structs have holes in them so we end up disclosing a few bytes of >>> uninitialized stack data. >>> >>> drivers/misc/xilinx_sdfec.c:305 xsdfec_get_status() warn: check that 'status' doesn't leak information (struct has a hole after 'activity') >>> drivers/misc/xilinx_sdfec.c:449 xsdfec_get_turbo() warn: check that 'turbo_params' doesn't leak information (struct has a hole after 'scale') >> >> Who is generating these warnings? Is this any new GCC or different tool? >> I see that 3byte padding but never seen these warnings. > > This is a Smatch check. ok. It looks like I need to update it to latest version. My version is not showing these. Anyway thanks for patches, Michal
Hi Dan, > -----Original Message----- > From: Dan Carpenter [mailto:dan.carpenter@oracle.com] > Sent: Wednesday 21 August 2019 08:06 > To: Derek Kiernan <dkiernan@xilinx.com>; Dragan Cvetic <draganc@xilinx.com> > Cc: Arnd Bergmann <arnd@arndb.de>; Greg Kroah-Hartman <gregkh@linuxfoundation.org>; Michal Simek <michals@xilinx.com>; > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org; kernel-janitors@vger.kernel.org > Subject: [PATCH 1/4] misc: xilinx_sdfec: Fix a couple small information leaks > > These structs have holes in them so we end up disclosing a few bytes of > uninitialized stack data. > > drivers/misc/xilinx_sdfec.c:305 xsdfec_get_status() warn: check that 'status' doesn't leak information (struct has a hole after 'activity') > drivers/misc/xilinx_sdfec.c:449 xsdfec_get_turbo() warn: check that 'turbo_params' doesn't leak information (struct has a hole after > 'scale') > > We need to zero out the holes with memset(). > > Fixes: 6bd6a690c2e7 ("misc: xilinx_sdfec: Add stats & status ioctls") > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > --- > drivers/misc/xilinx_sdfec.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c > index 912e939dec62..dc1b8b412712 100644 > --- a/drivers/misc/xilinx_sdfec.c > +++ b/drivers/misc/xilinx_sdfec.c > @@ -295,6 +295,7 @@ static int xsdfec_get_status(struct xsdfec_dev *xsdfec, void __user *arg) > struct xsdfec_status status; > int err; > > + memset(&status, 0, sizeof(status)); > spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags); > status.state = xsdfec->state; > xsdfec->state_updated = false; > @@ -440,6 +441,7 @@ static int xsdfec_get_turbo(struct xsdfec_dev *xsdfec, void __user *arg) > if (xsdfec->config.code == XSDFEC_LDPC_CODE) > return -EIO; > > + memset(&turbo_params, 0, sizeof(turbo_params)); > reg_value = xsdfec_regread(xsdfec, XSDFEC_TURBO_ADDR); > > turbo_params.scale = (reg_value & XSDFEC_TURBO_SCALE_MASK) >> > -- > 2.20.1 Reviewed-by: Dragan Cvetic <dragan.cvetic@xilinx.com> Thanks, Dragan
diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c index 912e939dec62..dc1b8b412712 100644 --- a/drivers/misc/xilinx_sdfec.c +++ b/drivers/misc/xilinx_sdfec.c @@ -295,6 +295,7 @@ static int xsdfec_get_status(struct xsdfec_dev *xsdfec, void __user *arg) struct xsdfec_status status; int err; + memset(&status, 0, sizeof(status)); spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags); status.state = xsdfec->state; xsdfec->state_updated = false; @@ -440,6 +441,7 @@ static int xsdfec_get_turbo(struct xsdfec_dev *xsdfec, void __user *arg) if (xsdfec->config.code == XSDFEC_LDPC_CODE) return -EIO; + memset(&turbo_params, 0, sizeof(turbo_params)); reg_value = xsdfec_regread(xsdfec, XSDFEC_TURBO_ADDR); turbo_params.scale = (reg_value & XSDFEC_TURBO_SCALE_MASK) >>
These structs have holes in them so we end up disclosing a few bytes of uninitialized stack data. drivers/misc/xilinx_sdfec.c:305 xsdfec_get_status() warn: check that 'status' doesn't leak information (struct has a hole after 'activity') drivers/misc/xilinx_sdfec.c:449 xsdfec_get_turbo() warn: check that 'turbo_params' doesn't leak information (struct has a hole after 'scale') We need to zero out the holes with memset(). Fixes: 6bd6a690c2e7 ("misc: xilinx_sdfec: Add stats & status ioctls") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- drivers/misc/xilinx_sdfec.c | 2 ++ 1 file changed, 2 insertions(+)