diff options
| author | Alexey Gladkov <gladkov.alexey@gmail.com> | 2020-05-18 20:07:38 +0200 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2020-05-19 07:07:50 -0500 |
| commit | 9d78edeaec759f997c303f286ecd39daee166f2a (patch) | |
| tree | 2325279bb24196709e59a506cbf4f346c1e69a2b /include/linux/proc_fs.h | |
| parent | 2dd8083f6d8acd1371ccabedef1c9f1ad272a90d (diff) | |
proc: proc_pid_ns takes super_block as an argument
syzbot found that
touch /proc/testfile
causes NULL pointer dereference at tomoyo_get_local_path()
because inode of the dentry is NULL.
Before c59f415a7cb6, Tomoyo received pid_ns from proc's s_fs_info
directly. Since proc_pid_ns() can only work with inode, using it in
the tomoyo_get_local_path() was wrong.
To avoid creating more functions for getting proc_ns, change the
argument type of the proc_pid_ns() function. Then, Tomoyo can use
the existing super_block to get pid_ns.
Link: https://lkml.kernel.org/r/0000000000002f0c7505a5b0e04c@google.com
Link: https://lkml.kernel.org/r/20200518180738.2939611-1-gladkov.alexey@gmail.com
Reported-by: syzbot+c1af344512918c61362c@syzkaller.appspotmail.com
Fixes: c59f415a7cb6 ("Use proc_pid_ns() to get pid_namespace from the proc superblock")
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Diffstat (limited to 'include/linux/proc_fs.h')
| -rw-r--r-- | include/linux/proc_fs.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index 2cb424e6f36a..6ec524d8842c 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -202,9 +202,9 @@ int open_related_ns(struct ns_common *ns, struct ns_common *(*get_ns)(struct ns_common *ns)); /* get the associated pid namespace for a file in procfs */ -static inline struct pid_namespace *proc_pid_ns(const struct inode *inode) +static inline struct pid_namespace *proc_pid_ns(struct super_block *sb) { - return proc_sb_info(inode->i_sb)->pid_ns; + return proc_sb_info(sb)->pid_ns; } #endif /* _LINUX_PROC_FS_H */ |