From patchwork Thu Jul 23 19:22:30 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: cifs: fix error handling in mount-time DFS referral chasing code Date: Thu, 23 Jul 2009 09:22:30 -0000 From: Jeff Layton X-Patchwork-Id: 30149 Message-Id: <1248376950-12366-1-git-send-email-jlayton@redhat.com> To: smfrench@gmail.com Cc: sm@sandro-mathys.ch, linux-cifs-client@lists.samba.org If the referral is malformed or the hostname can't be resolved, then the current code generates an oops. Fix it to handle these errors gracefully. Reported-by: Sandro Mathys Signed-off-by: Jeff Layton Acked-by: Igor Mammedov --- fs/cifs/cifs_dfs_ref.c | 12 +++++++++--- fs/cifs/connect.c | 13 ++++++++++--- 2 files changed, 19 insertions(+), 6 deletions(-) diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c index 3bb11be..606912d 100644 --- a/fs/cifs/cifs_dfs_ref.c +++ b/fs/cifs/cifs_dfs_ref.c @@ -55,7 +55,7 @@ void cifs_dfs_release_automount_timer(void) * i.e. strips from UNC trailing path that is not part of share * name and fixup missing '\' in the begining of DFS node refferal * if neccessary. - * Returns pointer to share name on success or NULL on error. + * Returns pointer to share name on success or ERR_PTR on error. * Caller is responsible for freeing returned string. */ static char *cifs_get_share_name(const char *node_name) @@ -68,7 +68,7 @@ static char *cifs_get_share_name(const char *node_name) UNC = kmalloc(len+2 /*for term null and additional \ if it's missed */, GFP_KERNEL); if (!UNC) - return NULL; + return ERR_PTR(-ENOMEM); /* get share name and server name */ if (node_name[1] != '\\') { @@ -87,7 +87,7 @@ static char *cifs_get_share_name(const char *node_name) cERROR(1, ("%s: no server name end in node name: %s", __func__, node_name)); kfree(UNC); - return NULL; + return ERR_PTR(-EINVAL); } /* find sharename end */ @@ -133,6 +133,12 @@ char *cifs_compose_mount_options(const char *sb_mountdata, return ERR_PTR(-EINVAL); *devname = cifs_get_share_name(ref->node_name); + if (IS_ERR(*devname)) { + rc = PTR_ERR(*devname); + *devname = NULL; + goto compose_mount_options_err; + } + rc = dns_resolve_server_name_to_ip(*devname, &srvIP); if (rc != 0) { cERROR(1, ("%s: Failed to resolve server part of %s to IP: %d", diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index fc44d31..f248688 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -2544,11 +2544,20 @@ remote_path_check: if (mount_data != mount_data_global) kfree(mount_data); + mount_data = cifs_compose_mount_options( cifs_sb->mountdata, full_path + 1, referrals, &fake_devname); - kfree(fake_devname); + free_dfs_info_array(referrals, num_referrals); + kfree(fake_devname); + kfree(full_path); + + if (IS_ERR(mount_data)) { + rc = PTR_ERR(mount_data); + mount_data = NULL; + goto mount_fail_check; + } if (tcon) cifs_put_tcon(tcon); @@ -2556,8 +2565,6 @@ remote_path_check: cifs_put_smb_ses(pSesInfo); cleanup_volume_info(&volume_info); - FreeXid(xid); - kfree(full_path); referral_walks_count++; goto try_mount_again; }