From 5faf153ebf6128f02ad6ffa2e8bbc9d823ef762c Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sat, 15 Jun 2013 05:49:36 +0400
Subject: [PATCH] don't call file_pos_write() if vfs_{read,write}{,v}() fails
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
fs/read_write.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/fs/read_write.c b/fs/read_write.c
index abca7437d1924..f646c8b565b91 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -477,7 +477,8 @@ SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
if (f.file) {
loff_t pos = file_pos_read(f.file);
ret = vfs_read(f.file, buf, count, &pos);
- file_pos_write(f.file, pos);
+ if (ret >= 0)
+ file_pos_write(f.file, pos);
fdput(f);
}
return ret;
@@ -492,7 +493,8 @@ SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf,
if (f.file) {
loff_t pos = file_pos_read(f.file);
ret = vfs_write(f.file, buf, count, &pos);
- file_pos_write(f.file, pos);
+ if (ret >= 0)
+ file_pos_write(f.file, pos);
fdput(f);
}
@@ -780,7 +782,8 @@ SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec,
if (f.file) {
loff_t pos = file_pos_read(f.file);
ret = vfs_readv(f.file, vec, vlen, &pos);
- file_pos_write(f.file, pos);
+ if (ret >= 0)
+ file_pos_write(f.file, pos);
fdput(f);
}
@@ -799,7 +802,8 @@ SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec,
if (f.file) {
loff_t pos = file_pos_read(f.file);
ret = vfs_writev(f.file, vec, vlen, &pos);
- file_pos_write(f.file, pos);
+ if (ret >= 0)
+ file_pos_write(f.file, pos);
fdput(f);
}
@@ -959,7 +963,8 @@ COMPAT_SYSCALL_DEFINE3(readv, unsigned long, fd,
return -EBADF;
pos = f.file->f_pos;
ret = compat_readv(f.file, vec, vlen, &pos);
- f.file->f_pos = pos;
+ if (ret >= 0)
+ f.file->f_pos = pos;
fdput(f);
return ret;
}
@@ -1025,7 +1030,8 @@ COMPAT_SYSCALL_DEFINE3(writev, unsigned long, fd,
return -EBADF;
pos = f.file->f_pos;
ret = compat_writev(f.file, vec, vlen, &pos);
- f.file->f_pos = pos;
+ if (ret >= 0)
+ f.file->f_pos = pos;
fdput(f);
return ret;
}
--
2.30.2