| Message ID | 1357911348-28403-1-git-send-email-marex@denx.de |
|---|---|
| State | Accepted |
| Delegated to: | Tom Rini |
| Headers | show |
2013/1/11 Marek Vasut <marex@denx.de>: > In case a function argument is known/fixed size array in C, the argument is > still decoyed as pointer instead ( T f(U n[k]) ~= T fn(U *n) ) and therefore > calling sizeof on the function argument will result in the size of the pointer, > not the size of the array. > > The VFAT code contains such a bug, this patch fixes it. > > Reported-by: Aaron Williams <Aaron.Williams@cavium.com> > Signed-off-by: Marek Vasut <marex@denx.de> > Cc: Tom Rini <tom.rini@gmail.com> > Cc: Aaron Williams <Aaron.Williams@cavium.com> > --- > fs/fat/fat.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) Tested-by: Michal Simek <michal.simek@xilinx.com> Thanks, Michal
On Fri, Jan 11, 2013 at 7:35 AM, Marek Vasut <marex@denx.de> wrote: > In case a function argument is known/fixed size array in C, the argument is > still decoyed as pointer instead ( T f(U n[k]) ~= T fn(U *n) ) and therefore > calling sizeof on the function argument will result in the size of the pointer, > not the size of the array. > > The VFAT code contains such a bug, this patch fixes it. > > Reported-by: Aaron Williams <Aaron.Williams@cavium.com> > Signed-off-by: Marek Vasut <marex@denx.de> > Cc: Tom Rini <tom.rini@gmail.com> > Cc: Aaron Williams <Aaron.Williams@cavium.com> > --- > fs/fat/fat.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/fs/fat/fat.c b/fs/fat/fat.c > index 393c378..25d3318 100644 > --- a/fs/fat/fat.c > +++ b/fs/fat/fat.c > @@ -569,9 +569,9 @@ static __u8 mkcksum(const char name[8], const char ext[3]) > > __u8 ret = 0; > > - for (i = 0; i < sizeof(name); i++) > + for (i = 0; i < 8; i++) > ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + name[i]; > - for (i = 0; i < sizeof(ext); i++) > + for (i = 0; i < 3; i++) > ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + ext[i]; > > return ret; Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
On Fri, Jan 11, 2013 at 03:35:48AM -0000, Marek Vasut wrote: > In case a function argument is known/fixed size array in C, the argument is > still decoyed as pointer instead ( T f(U n[k]) ~= T fn(U *n) ) and therefore > calling sizeof on the function argument will result in the size of the pointer, > not the size of the array. > > The VFAT code contains such a bug, this patch fixes it. > > Reported-by: Aaron Williams <Aaron.Williams@cavium.com> > Signed-off-by: Marek Vasut <marex@denx.de> > Cc: Tom Rini <tom.rini@gmail.com> > Cc: Aaron Williams <Aaron.Williams@cavium.com> > Tested-by: Michal Simek <michal.simek@xilinx.com> > Reviewed-by: Joe Hershberger <joe.hershberger@ni.com> Applied to u-boot/master, thanks!
Dear Tom Rini, > On Fri, Jan 11, 2013 at 03:35:48AM -0000, Marek Vasut wrote: > > In case a function argument is known/fixed size array in C, the argument > > is still decoyed as pointer instead ( T f(U n[k]) ~= T fn(U *n) ) and > > therefore calling sizeof on the function argument will result in the > > size of the pointer, not the size of the array. > > > > The VFAT code contains such a bug, this patch fixes it. > > > > Reported-by: Aaron Williams <Aaron.Williams@cavium.com> > > Signed-off-by: Marek Vasut <marex@denx.de> > > Cc: Tom Rini <tom.rini@gmail.com> > > Cc: Aaron Williams <Aaron.Williams@cavium.com> > > Tested-by: Michal Simek <michal.simek@xilinx.com> > > Reviewed-by: Joe Hershberger <joe.hershberger@ni.com> > > Applied to u-boot/master, thanks! Can we have a bugfix release 2013.02 or something ? This is a grave bug. Best regards, Marek Vasut
diff --git a/fs/fat/fat.c b/fs/fat/fat.c index 393c378..25d3318 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -569,9 +569,9 @@ static __u8 mkcksum(const char name[8], const char ext[3]) __u8 ret = 0; - for (i = 0; i < sizeof(name); i++) + for (i = 0; i < 8; i++) ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + name[i]; - for (i = 0; i < sizeof(ext); i++) + for (i = 0; i < 3; i++) ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + ext[i]; return ret;
In case a function argument is known/fixed size array in C, the argument is still decoyed as pointer instead ( T f(U n[k]) ~= T fn(U *n) ) and therefore calling sizeof on the function argument will result in the size of the pointer, not the size of the array. The VFAT code contains such a bug, this patch fixes it. Reported-by: Aaron Williams <Aaron.Williams@cavium.com> Signed-off-by: Marek Vasut <marex@denx.de> Cc: Tom Rini <tom.rini@gmail.com> Cc: Aaron Williams <Aaron.Williams@cavium.com> --- fs/fat/fat.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)