diff options
| author | Aurelien Jarno <aurelien@aurel32.net> | 2018-12-06 20:05:34 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-04-05 22:29:10 +0200 |
| commit | 24c6f9fdf8569bc5fec860baa9e6f9a1aee31dbf (patch) | |
| tree | 5565441e92b08f32d5445ca3f00c5eea32147e79 /fs/read_write.c | |
| parent | 97ac96eec621e861bdc5233db3ed2dcf1ba1a408 (diff) | |
vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1
[ Upstream commit cc4b1242d7e3b42eed73881fc749944146493e4f ]
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 <viro@zeniv.linux.org.uk>
Cc: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs/read_write.c')
| -rw-r--r-- | fs/read_write.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/read_write.c b/fs/read_write.c index 9819f7c6c8c5..6ab67b860159 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1204,6 +1204,9 @@ COMPAT_SYSCALL_DEFINE5(preadv64v2, unsigned long, fd, const struct compat_iovec __user *,vec, unsigned long, vlen, loff_t, pos, int, flags) { + if (pos == -1) + return do_compat_readv(fd, vec, vlen, flags); + return do_compat_preadv64(fd, vec, vlen, pos, flags); } #endif @@ -1310,6 +1313,9 @@ COMPAT_SYSCALL_DEFINE5(pwritev64v2, unsigned long, fd, const struct compat_iovec __user *,vec, unsigned long, vlen, loff_t, pos, int, flags) { + if (pos == -1) + return do_compat_writev(fd, vec, vlen, flags); + return do_compat_pwritev64(fd, vec, vlen, pos, flags); } #endif |