On Tue, Jun 15, 2021 at 9:21 AM Leon Romanovsky <leon@xxxxxxxxxx> wrote:
>
> The commit 591a22c14d3f ("proc: Track /proc/$pid/attr/ opener mm_struct")
> that we got in v5.13-rc6 broke our regression to pieces. The NIC interfaces
> fail to start when using NetworkManager.
Does the attached patch fix it?
It just makes the open always succeed, and then the private_data that
the open did (that may or may not then have been filled in) is only
used on write.
Linus
fs/proc/base.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 7118ebe38fa6..9cbd915025ad 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2676,7 +2676,9 @@ static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
#ifdef CONFIG_SECURITY
static int proc_pid_attr_open(struct inode *inode, struct file *file)
{
- return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
+ file->private_data = NULL;
+ __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
+ return 0;
}
static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
