2018-12-06 19:29:17

by Aurelien Jarno

Subject: [PATCH] vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1

The preadv2 and pwritev2 syscalls are supposed to emulate the readv and
writev syscalls when offset == -1. Therefore the compat code should
check for offset before calling do_compat_preadv64 and
do_compat_pwritev64. This is the case for the preadv2 and pwritev2
syscalls, but handling of offset == -1 is missing in their 64-bit
equivalent.

This patch fixes that, calling do_compat_readv and do_compat_writev when
offset == -1. This fixes the following glibc tests on x32:
- misc/tst-preadvwritev2
- misc/tst-preadvwritev64v2

Cc: Alexander Viro <[email protected]>
Cc: H.J. Lu <[email protected]>
Signed-off-by: Aurelien Jarno <[email protected]>
---
fs/read_write.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/fs/read_write.c b/fs/read_write.c
index 4dae0399c75a..c2dd3737fea2 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1241,6 +1241,9 @@ COMPAT_SYSCALL_DEFINE5(preadv64v2, unsigned long, fd,
const struct compat_iovec __user *,vec,
unsigned long, vlen, loff_t, pos, rwf_t, flags)
{
+ if (pos == -1)
+ return do_compat_readv(fd, vec, vlen, flags);
+
return do_compat_preadv64(fd, vec, vlen, pos, flags);
}
#endif
@@ -1347,6 +1350,9 @@ COMPAT_SYSCALL_DEFINE5(pwritev64v2, unsigned long, fd,
const struct compat_iovec __user *,vec,
unsigned long, vlen, loff_t, pos, rwf_t, flags)
{
+ if (pos == -1)
+ return do_compat_writev(fd, vec, vlen, flags);
+
return do_compat_pwritev64(fd, vec, vlen, pos, flags);
}
#endif
--
2.19.1

2019-01-12 20:55:15

by Aurelien Jarno

Subject: Re: [PATCH] vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1

On 2018-12-06 20:05, Aurelien Jarno wrote:
> The preadv2 and pwritev2 syscalls are supposed to emulate the readv and
> writev syscalls when offset == -1. Therefore the compat code should
> check for offset before calling do_compat_preadv64 and
> do_compat_pwritev64. This is the case for the preadv2 and pwritev2
> syscalls, but handling of offset == -1 is missing in their 64-bit
> equivalent.
>
> This patch fixes that, calling do_compat_readv and do_compat_writev when
> offset == -1. This fixes the following glibc tests on x32:
> - misc/tst-preadvwritev2
> - misc/tst-preadvwritev64v2
>
> Cc: Alexander Viro <[email protected]>
> Cc: H.J. Lu <[email protected]>
> Signed-off-by: Aurelien Jarno <[email protected]>
> ---
> fs/read_write.c | 6 ++++++
> 1 file changed, 6 insertions(+)

Any news about this patch?

Thanks,
Aurelien

--
Aurelien Jarno GPG: 4096R/1DDD8C9B
[email protected] http://www.aurel32.net

2019-02-17 04:47:34

by Aurelien Jarno

Subject: Re: [PATCH] vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1

On 2019-01-12 20:07, Aurelien Jarno wrote:
> On 2018-12-06 20:05, Aurelien Jarno wrote:
> > The preadv2 and pwritev2 syscalls are supposed to emulate the readv and
> > writev syscalls when offset == -1. Therefore the compat code should
> > check for offset before calling do_compat_preadv64 and
> > do_compat_pwritev64. This is the case for the preadv2 and pwritev2
> > syscalls, but handling of offset == -1 is missing in their 64-bit
> > equivalent.
> >
> > This patch fixes that, calling do_compat_readv and do_compat_writev when
> > offset == -1. This fixes the following glibc tests on x32:
> > - misc/tst-preadvwritev2
> > - misc/tst-preadvwritev64v2
> >
> > Cc: Alexander Viro <[email protected]>
> > Cc: H.J. Lu <[email protected]>
> > Signed-off-by: Aurelien Jarno <[email protected]>
> > ---
> > fs/read_write.c | 6 ++++++
> > 1 file changed, 6 insertions(+)
>
> Any news about this patch?
>

Ping.

Aurelien

--
Aurelien Jarno GPG: 4096R/1DDD8C9B
[email protected] http://www.aurel32.net

2019-02-17 05:35:27

by Al Viro

Subject: Re: [PATCH] vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1

On Sat, Feb 16, 2019 at 04:15:28PM +0100, Aurelien Jarno wrote:
> On 2019-01-12 20:07, Aurelien Jarno wrote:
> > On 2018-12-06 20:05, Aurelien Jarno wrote:
> > > The preadv2 and pwritev2 syscalls are supposed to emulate the readv and
> > > writev syscalls when offset == -1. Therefore the compat code should
> > > check for offset before calling do_compat_preadv64 and
> > > do_compat_pwritev64. This is the case for the preadv2 and pwritev2
> > > syscalls, but handling of offset == -1 is missing in their 64-bit
> > > equivalent.
> > >
> > > This patch fixes that, calling do_compat_readv and do_compat_writev when
> > > offset == -1. This fixes the following glibc tests on x32:
> > > - misc/tst-preadvwritev2
> > > - misc/tst-preadvwritev64v2
> > >
> > > Cc: Alexander Viro <[email protected]>
> > > Cc: H.J. Lu <[email protected]>
> > > Signed-off-by: Aurelien Jarno <[email protected]>
> > > ---
> > > fs/read_write.c | 6 ++++++
> > > 1 file changed, 6 insertions(+)
> >
> > Any news about this patch?
> >
>
> Ping.

Applied