mirrors/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2025-11-04 02:30:34 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

commoncap: move assignment of fs_ns to avoid null pointer dereference

Browse source 
The pointer fs_ns is assigned from inode->i_ib->s_user_ns before
a null pointer check on inode, hence if inode is actually null we
will get a null pointer dereference on this assignment. Fix this
by only dereferencing inode after the null pointer check on
inode.

Detected by CoverityScan CID#1455328 ("Dereference before null check")

Fixes: 8db6c34f1d ("Introduce v3 namespaced file capabilities")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: stable@vger.kernel.org
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
This commit is contained in:
Colin Ian King 2017-09-04 18:50:05 +01:00 committed by James Morris
parent 494b9ae7ab
commit 76ba89c76f
1 changed files with 2 additions and 1 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

3
security/commoncap.c
View file

@ -585,13 +585,14 @@ int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data
struct vfs_ns_cap_data data, *nscaps = &data; struct vfs_ns_cap_data data, *nscaps = &data;
struct vfs_cap_data *caps = (struct vfs_cap_data *) &data; struct vfs_cap_data *caps = (struct vfs_cap_data *) &data;
kuid_t rootkuid; kuid_t rootkuid;
struct user_namespace *fs_ns = inode->i_sb->s_user_ns; struct user_namespace *fs_ns;
memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data)); memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data));
if (!inode) if (!inode)
return -ENODATA; return -ENODATA;
fs_ns = inode->i_sb->s_user_ns;
size = __vfs_getxattr((struct dentry *)dentry, inode, size = __vfs_getxattr((struct dentry *)dentry, inode,
XATTR_NAME_CAPS, &data, XATTR_CAPS_SZ); XATTR_NAME_CAPS, &data, XATTR_CAPS_SZ);
if (size == -ENODATA || size == -EOPNOTSUPP) if (size == -ENODATA || size == -EOPNOTSUPP)