From 9b4f526cdc0f95f635607dfba6ac788b3deca188 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 22 Apr 2008 01:32:44 -0400 Subject: [PATCH] [PATCH] proc_readfd_common() race fix Since we drop the rcu_read_lock inside the loop, we can't assume that files->fdt will remain unchanged (and not freed) between iterations. Signed-off-by: Al Viro --- fs/proc/base.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 81d7d145292a..7313c62e3e9d 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1626,7 +1626,6 @@ static int proc_readfd_common(struct file * filp, void * dirent, unsigned int fd, ino; int retval; struct files_struct * files; - struct fdtable *fdt; retval = -ENOENT; if (!p) @@ -1649,9 +1648,8 @@ static int proc_readfd_common(struct file * filp, void * dirent, if (!files) goto out; rcu_read_lock(); - fdt = files_fdtable(files); for (fd = filp->f_pos-2; - fd < fdt->max_fds; + fd < files_fdtable(files)->max_fds; fd++, filp->f_pos++) { char name[PROC_NUMBUF]; int len;