| Message ID | 20200617175647.GA26370@embeddedor (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [next] fbdev/fb.h: Use struct_size() helper in kzalloc() | expand |
Hi Gustavo. On Wed, Jun 17, 2020 at 12:56:47PM -0500, Gustavo A. R. Silva wrote: > Make use of the struct_size() helper instead of an open-coded version > in order to avoid any potential type mistakes. > > This code was detected with the help of Coccinelle and, audited and > fixed manually. > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> struct_size is defined in overflow.h - which is not included by fs.h. So we rely on overflow.h being pulled in by some other header - maybe slab.h in this case. Seems fragile, should this patch add an include of overflow.h? Sam > --- > include/linux/fb.h | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/include/linux/fb.h b/include/linux/fb.h > index 3b4b2f0c6994..2b530e6d86e4 100644 > --- a/include/linux/fb.h > +++ b/include/linux/fb.h > @@ -506,8 +506,9 @@ struct fb_info { > }; > > static inline struct apertures_struct *alloc_apertures(unsigned int max_num) { > - struct apertures_struct *a = kzalloc(sizeof(struct apertures_struct) > - + max_num * sizeof(struct aperture), GFP_KERNEL); > + struct apertures_struct *a; > + > + a = kzalloc(struct_size(a, ranges, max_num), GFP_KERNEL); > if (!a) > return NULL; > a->count = max_num; > -- > 2.27.0 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
On 6/17/20 7:56 PM, Gustavo A. R. Silva wrote: > Make use of the struct_size() helper instead of an open-coded version > in order to avoid any potential type mistakes. > > This code was detected with the help of Coccinelle and, audited and > fixed manually. > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Applied to drm-misc-next tree, thanks. Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics > --- > include/linux/fb.h | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/include/linux/fb.h b/include/linux/fb.h > index 3b4b2f0c6994..2b530e6d86e4 100644 > --- a/include/linux/fb.h > +++ b/include/linux/fb.h > @@ -506,8 +506,9 @@ struct fb_info { > }; > > static inline struct apertures_struct *alloc_apertures(unsigned int max_num) { > - struct apertures_struct *a = kzalloc(sizeof(struct apertures_struct) > - + max_num * sizeof(struct aperture), GFP_KERNEL); > + struct apertures_struct *a; > + > + a = kzalloc(struct_size(a, ranges, max_num), GFP_KERNEL); > if (!a) > return NULL; > a->count = max_num; >
On 6/20/20 1:27 PM, Sam Ravnborg wrote: > Hi Gustavo. > > On Wed, Jun 17, 2020 at 12:56:47PM -0500, Gustavo A. R. Silva wrote: >> Make use of the struct_size() helper instead of an open-coded version >> in order to avoid any potential type mistakes. >> >> This code was detected with the help of Coccinelle and, audited and >> fixed manually. >> >> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> > > struct_size is defined in overflow.h - which is not included by fs.h. > So we rely on overflow.h being pulled in by some other header - maybe > slab.h in this case. > Seems fragile, should this patch add an include of overflow.h? $ git grep struct_size drivers/|wc -l 697 $ git grep overflow\\.h drivers/|wc -l 8 $ git grep overflow\\.h include/linux/ include/linux/device.h:#include <linux/overflow.h> include/linux/mm.h:#include <linux/overflow.h> include/linux/slab.h:#include <linux/overflow.h> include/linux/vmalloc.h:#include <linux/overflow.h> so I've applied the patch as it is (hoping that the issue is so widespread that no-one tries to remove overflow.h from slab.h without fixing drivers at the same time).. Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics > Sam > >> --- >> include/linux/fb.h | 5 +++-- >> 1 file changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/include/linux/fb.h b/include/linux/fb.h >> index 3b4b2f0c6994..2b530e6d86e4 100644 >> --- a/include/linux/fb.h >> +++ b/include/linux/fb.h >> @@ -506,8 +506,9 @@ struct fb_info { >> }; >> >> static inline struct apertures_struct *alloc_apertures(unsigned int max_num) { >> - struct apertures_struct *a = kzalloc(sizeof(struct apertures_struct) >> - + max_num * sizeof(struct aperture), GFP_KERNEL); >> + struct apertures_struct *a; >> + >> + a = kzalloc(struct_size(a, ranges, max_num), GFP_KERNEL); >> if (!a) >> return NULL; >> a->count = max_num; >> -- >> 2.27.0 >> >> _______________________________________________ >> dri-devel mailing list >> dri-devel@lists.freedesktop.org >> https://protect2.fireeye.com/url?k=7bae4d09-26604cda-7bafc646-000babff317b-7eab3a2caa4b8b73&q=1&u=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fdri-devel
diff --git a/include/linux/fb.h b/include/linux/fb.h index 3b4b2f0c6994..2b530e6d86e4 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -506,8 +506,9 @@ struct fb_info { }; static inline struct apertures_struct *alloc_apertures(unsigned int max_num) { - struct apertures_struct *a = kzalloc(sizeof(struct apertures_struct) - + max_num * sizeof(struct aperture), GFP_KERNEL); + struct apertures_struct *a; + + a = kzalloc(struct_size(a, ranges, max_num), GFP_KERNEL); if (!a) return NULL; a->count = max_num;
Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes. This code was detected with the help of Coccinelle and, audited and fixed manually. Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- include/linux/fb.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)