From f6500801522c61782d4990fa1ad96154cb397cd4 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 26 Jan 2014 12:37:55 -0500 Subject: __dentry_path() fixes * we need to save the starting point for restarts * reject pathologically short buffers outright Spotted-by: Denys Vlasenko Spotted-by: Oleg Nesterov Signed-off-by: Al Viro --- fs/dcache.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index fdbe23027810..265e0ce9769c 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -3116,19 +3116,22 @@ char *simple_dname(struct dentry *dentry, char *buffer, int buflen) /* * Write full pathname from the root of the filesystem into the buffer. */ -static char *__dentry_path(struct dentry *dentry, char *buf, int buflen) +static char *__dentry_path(struct dentry *d, char *buf, int buflen) { + struct dentry *dentry; char *end, *retval; int len, seq = 0; int error = 0; + if (buflen < 2) + goto Elong; + rcu_read_lock(); restart: + dentry = d; end = buf + buflen; len = buflen; prepend(&end, &len, "\0", 1); - if (buflen < 1) - goto Elong; /* Get '/' right */ retval = end-1; *retval = '/'; -- cgit v1.2.1