path: root/fs
diff options
authorYann Droneaud <ydroneaud@opteya.com>2015-06-30 14:57:33 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-30 19:44:57 -0700
commit189f9841de23a58ecb4b2602db8581512ff08ba4 (patch)
tree964d5a53219d3a89986518472c408253f4eaa1d4 /fs
parentede1bf0dcff2b07001c760992b1ca18fd0f419bc (diff)
fs: allocate structure unconditionally in seq_open()
Since patch described below, from v2.6.15-rc1, seq_open() could use a struct seq_file already allocated by the caller if the pointer to the structure is stored in file->private_data before calling the function. Commit 1abe77b0fc4b485927f1f798ae81a752677e1d05 Author: Al Viro <viro@zeniv.linux.org.uk> Date: Mon Nov 7 17:15:34 2005 -0500 [PATCH] allow callers of seq_open do allocation themselves Allow caller of seq_open() to kmalloc() seq_file + whatever else they want and set ->private_data to it. seq_open() will then abstain from doing allocation itself. As there's no more use for such feature, as it could be easily replaced by calls to seq_open_private() (see commit 39699037a5c9 ("[FS] seq_file: Introduce the seq_open_private()")) and seq_release_private() (see v2.6.0-test3), support for this uncommon feature can be removed from seq_open(). Link: http://lkml.kernel.org/r/cover.1433193673.git.ydroneaud@opteya.com Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
1 files changed, 9 insertions, 8 deletions
diff --git a/fs/seq_file.c b/fs/seq_file.c
index 555f82155be8..5f163c6c821c 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -51,15 +51,16 @@ static void *seq_buf_alloc(unsigned long size)
int seq_open(struct file *file, const struct seq_operations *op)
- struct seq_file *p = file->private_data;
+ struct seq_file *p;
+ WARN_ON(file->private_data);
+ p = kzalloc(sizeof(*p), GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+ file->private_data = p;
- if (!p) {
- p = kmalloc(sizeof(*p), GFP_KERNEL);
- if (!p)
- return -ENOMEM;
- file->private_data = p;
- }
- memset(p, 0, sizeof(*p));
p->op = op;