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| author | Christian Brauner <christian.brauner@ubuntu.com> | 2021-11-29 14:44:34 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-01-20 11:13:14 +0300 |
| commit | 7760404e848780c3b3a97b0026ce755b5f006687 (patch) | |
| tree | 1d8bcc211b67881686489306c01aab203fa3b3e4 /fs/9p | |
| parent | c2e7561ba7a89697785b0984a55c02f0d588ea80 (diff) | |
| download | linux-7760404e848780c3b3a97b0026ce755b5f006687.tar.xz | |
9p: only copy valid iattrs in 9P2000.L setattr implementation
commit 3cb6ee991496b67ee284c6895a0ba007e2d7bac3 upstream.
The 9P2000.L setattr method v9fs_vfs_setattr_dotl() copies struct iattr
values without checking whether they are valid causing unitialized
values to be copied. The 9P2000 setattr method v9fs_vfs_setattr() method
gets this right. Check whether struct iattr fields are valid first
before copying in v9fs_vfs_setattr_dotl() too and make sure that all
other fields are set to 0 apart from {g,u}id which should be set to
INVALID_{G,U}ID. This ensure that they can be safely sent over the wire
or printed for debugging later on.
Link: https://lkml.kernel.org/r/20211129114434.3637938-1-brauner@kernel.org
Link: https://lkml.kernel.org/r/000000000000a0d53f05d1c72a4c%40google.com
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: stable@kernel.org
Cc: v9fs-developer@lists.sourceforge.net
Reported-by: syzbot+dfac92a50024b54acaa4@syzkaller.appspotmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
[Dominique: do not set a/mtime with just ATTR_A/MTIME as discussed]
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/9p')
| -rw-r--r-- | fs/9p/vfs_inode_dotl.c | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c index 01b9e1281a29..a61df2e0ae52 100644 --- a/fs/9p/vfs_inode_dotl.c +++ b/fs/9p/vfs_inode_dotl.c @@ -553,7 +553,10 @@ int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns, { int retval, use_dentry = 0; struct p9_fid *fid = NULL; - struct p9_iattr_dotl p9attr; + struct p9_iattr_dotl p9attr = { + .uid = INVALID_UID, + .gid = INVALID_GID, + }; struct inode *inode = d_inode(dentry); p9_debug(P9_DEBUG_VFS, "\n"); @@ -563,14 +566,22 @@ int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns, return retval; p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid); - p9attr.mode = iattr->ia_mode; - p9attr.uid = iattr->ia_uid; - p9attr.gid = iattr->ia_gid; - p9attr.size = iattr->ia_size; - p9attr.atime_sec = iattr->ia_atime.tv_sec; - p9attr.atime_nsec = iattr->ia_atime.tv_nsec; - p9attr.mtime_sec = iattr->ia_mtime.tv_sec; - p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec; + if (iattr->ia_valid & ATTR_MODE) + p9attr.mode = iattr->ia_mode; + if (iattr->ia_valid & ATTR_UID) + p9attr.uid = iattr->ia_uid; + if (iattr->ia_valid & ATTR_GID) + p9attr.gid = iattr->ia_gid; + if (iattr->ia_valid & ATTR_SIZE) + p9attr.size = iattr->ia_size; + if (iattr->ia_valid & ATTR_ATIME_SET) { + p9attr.atime_sec = iattr->ia_atime.tv_sec; + p9attr.atime_nsec = iattr->ia_atime.tv_nsec; + } + if (iattr->ia_valid & ATTR_MTIME_SET) { + p9attr.mtime_sec = iattr->ia_mtime.tv_sec; + p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec; + } if (iattr->ia_valid & ATTR_FILE) { fid = iattr->ia_file->private_data; |