| Message ID | 20130116220153.GD18593@gmail.com |
|---|---|
| State | Superseded |
| Delegated to: | David Miller |
| Headers | show |
On 16/01/2013 22:01, Cong Ding wrote: > the variable iommu and strbuf are not freed if it goes to error. > > Signed-off-by: Cong Ding <dinggnu@gmail.com> > --- > arch/sparc/kernel/sbus.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/sparc/kernel/sbus.c b/arch/sparc/kernel/sbus.c > index 1271b3a..78aa26b 100644 > --- a/arch/sparc/kernel/sbus.c > +++ b/arch/sparc/kernel/sbus.c > @@ -656,6 +656,8 @@ static void __init sbus_iommu_init(struct platform_device *op) > return; > > fatal_memory_error: > + kfree(strbuf); strbuf will be uninitialized if the iommu allocation fails. I don't have a particular preference for how to fix this but tend to dislike initial assignment with NULL because it hides other control flow issues. Regards Richard > + kfree(iommu); > prom_printf("sbus_iommu_init: Fatal memory allocation error.\n"); > } > > -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jan 17, 2013 at 10:41:59AM +0000, Richard Mortimer wrote: > > > On 16/01/2013 22:01, Cong Ding wrote: > >the variable iommu and strbuf are not freed if it goes to error. > > > >Signed-off-by: Cong Ding <dinggnu@gmail.com> > >--- > > arch/sparc/kernel/sbus.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > >diff --git a/arch/sparc/kernel/sbus.c b/arch/sparc/kernel/sbus.c > >index 1271b3a..78aa26b 100644 > >--- a/arch/sparc/kernel/sbus.c > >+++ b/arch/sparc/kernel/sbus.c > >@@ -656,6 +656,8 @@ static void __init sbus_iommu_init(struct platform_device *op) > > return; > > > > fatal_memory_error: > >+ kfree(strbuf); > > strbuf will be uninitialized if the iommu allocation fails. I don't > have a particular preference for how to fix this but tend to dislike > initial assignment with NULL because it hides other control flow > issues. Sorry I didn't notice strbuf will be uninitialized here. But if we don't initially assign a NULL value to strbuf, I cannot find a way to handle it besides the first version patch. Did you have any suggestions? For me, I like the first version. - cong > > Regards > > Richard > > >+ kfree(iommu); > > prom_printf("sbus_iommu_init: Fatal memory allocation error.\n"); > > } > > > > -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 17/01/2013 11:56, Cong Ding wrote: > On Thu, Jan 17, 2013 at 10:41:59AM +0000, Richard Mortimer wrote: >> >> >> On 16/01/2013 22:01, Cong Ding wrote: >>> the variable iommu and strbuf are not freed if it goes to error. >>> >>> Signed-off-by: Cong Ding <dinggnu@gmail.com> >>> --- >>> arch/sparc/kernel/sbus.c | 2 ++ >>> 1 file changed, 2 insertions(+) >>> >>> diff --git a/arch/sparc/kernel/sbus.c b/arch/sparc/kernel/sbus.c >>> index 1271b3a..78aa26b 100644 >>> --- a/arch/sparc/kernel/sbus.c >>> +++ b/arch/sparc/kernel/sbus.c >>> @@ -656,6 +656,8 @@ static void __init sbus_iommu_init(struct platform_device *op) >>> return; >>> >>> fatal_memory_error: >>> + kfree(strbuf); >> >> strbuf will be uninitialized if the iommu allocation fails. I don't >> have a particular preference for how to fix this but tend to dislike >> initial assignment with NULL because it hides other control flow >> issues. > Sorry I didn't notice strbuf will be uninitialized here. But if we don't > initially assign a NULL value to strbuf, I cannot find a way to handle it > besides the first version patch. Did you have any suggestions? For me, I like > the first version. Two thoughts... 1 - just use a goto target for the iommu allocation failure and make that skip the strbuf free call. The others use the existing fatal_memory_error label. 2 - Move the strbuf kzalloc up 2 lines so that it occurs before the test for iommu. 2b - In case (2) above the failure test could be changed to if (!iommu || !strbuf) to remove duplication of goto. I'd probably go for 2/2b to address Sam's initial comment. Regards Richard > - cong >> >> Regards >> >> Richard >> >>> + kfree(iommu); >>> prom_printf("sbus_iommu_init: Fatal memory allocation error.\n"); >>> } >>> >>> -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jan 17, 2013 at 12:30:11PM +0000, Richard Mortimer wrote: > > > On 17/01/2013 11:56, Cong Ding wrote: > >On Thu, Jan 17, 2013 at 10:41:59AM +0000, Richard Mortimer wrote: > >> > >> > >>On 16/01/2013 22:01, Cong Ding wrote: > >>>the variable iommu and strbuf are not freed if it goes to error. > >>> > >>>Signed-off-by: Cong Ding <dinggnu@gmail.com> > >>>--- > >>> arch/sparc/kernel/sbus.c | 2 ++ > >>> 1 file changed, 2 insertions(+) > >>> > >>>diff --git a/arch/sparc/kernel/sbus.c b/arch/sparc/kernel/sbus.c > >>>index 1271b3a..78aa26b 100644 > >>>--- a/arch/sparc/kernel/sbus.c > >>>+++ b/arch/sparc/kernel/sbus.c > >>>@@ -656,6 +656,8 @@ static void __init sbus_iommu_init(struct platform_device *op) > >>> return; > >>> > >>> fatal_memory_error: > >>>+ kfree(strbuf); > >> > >>strbuf will be uninitialized if the iommu allocation fails. I don't > >>have a particular preference for how to fix this but tend to dislike > >>initial assignment with NULL because it hides other control flow > >>issues. > >Sorry I didn't notice strbuf will be uninitialized here. But if we don't > >initially assign a NULL value to strbuf, I cannot find a way to handle it > >besides the first version patch. Did you have any suggestions? For me, I like > >the first version. > > Two thoughts... > > 1 - just use a goto target for the iommu allocation failure and make > that skip the strbuf free call. The others use the existing > fatal_memory_error label. this looks ugly. If we do in this way, why not version 1? > > 2 - Move the strbuf kzalloc up 2 lines so that it occurs before the > test for iommu. > > 2b - In case (2) above the failure test could be changed to > if (!iommu || !strbuf) > to remove duplication of goto. I will send a new version by using this solution. Thanks, - cong -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/sparc/kernel/sbus.c b/arch/sparc/kernel/sbus.c index 1271b3a..78aa26b 100644 --- a/arch/sparc/kernel/sbus.c +++ b/arch/sparc/kernel/sbus.c @@ -656,6 +656,8 @@ static void __init sbus_iommu_init(struct platform_device *op) return; fatal_memory_error: + kfree(strbuf); + kfree(iommu); prom_printf("sbus_iommu_init: Fatal memory allocation error.\n"); }
the variable iommu and strbuf are not freed if it goes to error. Signed-off-by: Cong Ding <dinggnu@gmail.com> --- arch/sparc/kernel/sbus.c | 2 ++ 1 file changed, 2 insertions(+)