]> git.ipfire.org Git - thirdparty/kernel/stable-queue.git/commitdiff
4.4-stable patches
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 20 Jun 2019 16:49:18 +0000 (18:49 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 20 Jun 2019 16:49:18 +0000 (18:49 +0200)
added patches:
abort-file_remove_privs-for-non-reg.-files.patch

queue-4.4/abort-file_remove_privs-for-non-reg.-files.patch [new file with mode: 0644]
queue-4.4/series

diff --git a/queue-4.4/abort-file_remove_privs-for-non-reg.-files.patch b/queue-4.4/abort-file_remove_privs-for-non-reg.-files.patch
new file mode 100644 (file)
index 0000000..346bed2
--- /dev/null
@@ -0,0 +1,51 @@
+From f69e749a49353d96af1a293f56b5b56de59c668a Mon Sep 17 00:00:00 2001
+From: Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
+Date: Fri, 14 Dec 2018 11:55:52 +0100
+Subject: Abort file_remove_privs() for non-reg. files
+
+From: Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
+
+commit f69e749a49353d96af1a293f56b5b56de59c668a upstream.
+
+file_remove_privs() might be called for non-regular files, e.g.
+blkdev inode. There is no reason to do its job on things
+like blkdev inodes, pipes, or cdevs. Hence, abort if
+file does not refer to a regular inode.
+
+AV: more to the point, for devices there might be any number of
+inodes refering to given device.  Which one to strip the permissions
+from, even if that made any sense in the first place?  All of them
+will be observed with contents modified, after all.
+
+Found by LockDoc (Alexander Lochmann, Horst Schirmeier and Olaf
+Spinczyk)
+
+Reviewed-by: Jan Kara <jack@suse.cz>
+Signed-off-by: Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
+Signed-off-by: Horst Schirmeier <horst.schirmeier@tu-dortmund.de>
+Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
+Cc: Zubin Mithra <zsm@chromium.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/inode.c |    9 +++++++--
+ 1 file changed, 7 insertions(+), 2 deletions(-)
+
+--- a/fs/inode.c
++++ b/fs/inode.c
+@@ -1744,8 +1744,13 @@ int file_remove_privs(struct file *file)
+       int kill;
+       int error = 0;
+-      /* Fast path for nothing security related */
+-      if (IS_NOSEC(inode))
++      /*
++       * Fast path for nothing security related.
++       * As well for non-regular files, e.g. blkdev inodes.
++       * For example, blkdev_write_iter() might get here
++       * trying to remove privs which it is not allowed to.
++       */
++      if (IS_NOSEC(inode) || !S_ISREG(inode->i_mode))
+               return 0;
+       kill = dentry_needs_remove_privs(dentry);
index 8197be68b94c4560907e787f2a1885ee1349d8a7..3e31107c35597a6adb01b27a7ef60d64466b1ae7 100644 (file)
@@ -81,3 +81,4 @@ scsi-libcxgbi-add-a-check-for-null-pointer-in-cxgbi_.patch
 scsi-libsas-delete-sas-port-if-expander-discover-fai.patch
 revert-crypto-crypto4xx-properly-set-iv-after-de-and-encrypt.patch
 coredump-fix-race-condition-between-mmget_not_zero-get_task_mm-and-core-dumping.patch
+abort-file_remove_privs-for-non-reg.-files.patch