| From 7a89fb4e5e00658e935703737211032b909e23fa Mon Sep 17 00:00:00 2001 |
| From: Ronnie Sahlberg <lsahlber@redhat.com> |
| Date: Wed, 22 Jan 2020 11:07:56 +1000 |
| Subject: [PATCH] cifs: fix NULL dereference in match_prepath |
| |
| commit fe1292686333d1dadaf84091f585ee903b9ddb84 upstream. |
| |
| RHBZ: 1760879 |
| |
| Fix an oops in match_prepath() by making sure that the prepath string is not |
| NULL before we pass it into strcmp(). |
| |
| This is similar to other checks we make for example in cifs_root_iget() |
| |
| Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> |
| Signed-off-by: Steve French <stfrench@microsoft.com> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c |
| index eb619b3bce8f..238639887589 100644 |
| --- a/fs/cifs/connect.c |
| +++ b/fs/cifs/connect.c |
| @@ -3573,8 +3573,10 @@ match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data) |
| { |
| struct cifs_sb_info *old = CIFS_SB(sb); |
| struct cifs_sb_info *new = mnt_data->cifs_sb; |
| - bool old_set = old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH; |
| - bool new_set = new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH; |
| + bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) && |
| + old->prepath; |
| + bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) && |
| + new->prepath; |
| |
| if (old_set && new_set && !strcmp(new->prepath, old->prepath)) |
| return 1; |
| -- |
| 2.7.4 |
| |
