[PATCH 63/79] namei: we never need more than MAXSYMLINKS entries in nd->stack

From: Al Viro
Date: Tue May 05 2015 - 01:35:44 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

The only reason why we needed one more was that purely nested
MAXSYMLINKS symlinks could lead to path_init() using that many
entries in addition to nd->stack[0] which it left unused.

That can't happen now - path_init() starts with entry 0 (and
trailing_symlink() is called only when we'd already encountered
one symlink, so no more than MAXSYMLINKS-1 are left).

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/namei.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/namei.c b/fs/namei.c
index 85646cc..e4ca3b1 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -528,7 +528,7 @@ static void restore_nameidata(struct nameidata *nd)

static int __nd_alloc_stack(struct nameidata *nd)
{
- struct saved *p = kmalloc((MAXSYMLINKS + 1) * sizeof(struct saved),
+ struct saved *p = kmalloc(MAXSYMLINKS * sizeof(struct saved),
GFP_KERNEL);
if (unlikely(!p))
return -ENOMEM;
--
2.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/