From: Paulo Alcantara <pc@xxxxxxxxxxxxx>
commit 49024ec8795ed2bd7217c249ef50a70c4e25d662 upstream.
Handle trailing and leading separators when parsing UNC and prefix
paths in smb3_parse_devname(). Then, store the sanitised paths in
smb3_fs_context::source.
This fixes the following cases
$ mount //srv/share// /mnt/1 -o ...
$ cat /mnt/1/d0/f0
cat: /mnt/1/d0/f0: Invalid argument
The -EINVAL was returned because the client sent SMB2_CREATE "\\d0\f0"
rather than SMB2_CREATE "\d0\f0".
$ mount //srv//share /mnt/1 -o ...
mount: Invalid argument
The -EINVAL was returned correctly although the client only realised
it after sending a couple of bad requests rather than bailing out
earlier when parsing mount options.
Signed-off-by: Paulo Alcantara (SUSE) <pc@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/smb/client/cifs_dfs_ref.c | 20 ++++++++++----
fs/smb/client/cifsproto.h | 2 +
fs/smb/client/dfs.c | 38 ++-------------------------
fs/smb/client/fs_context.c | 59 ++++++++++++++++++++++++++++++++++++-------
fs/smb/client/misc.c | 17 ++++++++----
5 files changed, 80 insertions(+), 56 deletions(-)
--- a/fs/smb/client/cifs_dfs_ref.c
+++ b/fs/smb/client/cifs_dfs_ref.c
@@ -118,12 +118,12 @@ cifs_build_devname(char *nodename, const
return dev;
}
-static int set_dest_addr(struct smb3_fs_context *ctx, const char *full_path)
+static int set_dest_addr(struct smb3_fs_context *ctx)
{
struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
int rc;
- rc = dns_resolve_server_name_to_ip(full_path, addr, NULL);
+ rc = dns_resolve_server_name_to_ip(ctx->source, addr, NULL);
if (!rc)
cifs_set_port(addr, ctx->port);
return rc;
@@ -171,10 +171,9 @@ static struct vfsmount *cifs_dfs_do_auto
mnt = ERR_CAST(full_path);
goto out;
}
- cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
tmp = *cur_ctx;
- tmp.source = full_path;
+ tmp.source = NULL;
tmp.leaf_fullpath = NULL;
tmp.UNC = tmp.prepath = NULL;
tmp.dfs_root_ses = NULL;
@@ -185,13 +184,22 @@ static struct vfsmount *cifs_dfs_do_auto
goto out;
}
- rc = set_dest_addr(ctx, full_path);
+ rc = smb3_parse_devname(full_path, ctx);
if (rc) {
mnt = ERR_PTR(rc);
goto out;
}
- rc = smb3_parse_devname(full_path, ctx);
+ ctx->source = smb3_fs_context_fullpath(ctx, '/');
+ if (IS_ERR(ctx->source)) {
+ mnt = ERR_CAST(ctx->source);
+ ctx->source = NULL;
+ goto out;
+ }
+ cifs_dbg(FYI, "%s: ctx: source=%s UNC=%s prepath=%s dstaddr=%pISpc\n",
+ __func__, ctx->source, ctx->UNC, ctx->prepath, &ctx->dstaddr);
+
+ rc = set_dest_addr(ctx);
if (!rc)
mnt = fc_mount(fc);
else
--- a/fs/smb/client/cifsproto.h
+++ b/fs/smb/client/cifsproto.h
@@ -85,6 +85,8 @@ extern void release_mid(struct mid_q_ent
extern void cifs_wake_up_task(struct mid_q_entry *mid);
extern int cifs_handle_standard(struct TCP_Server_Info *server,
struct mid_q_entry *mid);
+extern char *smb3_fs_context_fullpath(const struct smb3_fs_context *ctx,
+ char dirsep);
extern int smb3_parse_devname(const char *devname, struct smb3_fs_context *ctx);
extern int smb3_parse_opt(const char *options, const char *key, char **val);
extern int cifs_ipaddr_cmp(struct sockaddr *srcaddr, struct sockaddr *rhs);
--- a/fs/smb/client/dfs.c
+++ b/fs/smb/client/dfs.c
@@ -54,39 +54,6 @@ out:
return rc;
}
-/*
- * cifs_build_path_to_root returns full path to root when we do not have an
- * existing connection (tcon)
- */
-static char *build_unc_path_to_root(const struct smb3_fs_context *ctx,
- const struct cifs_sb_info *cifs_sb, bool useppath)
-{
- char *full_path, *pos;
- unsigned int pplen = useppath && ctx->prepath ? strlen(ctx->prepath) + 1 : 0;
- unsigned int unc_len = strnlen(ctx->UNC, MAX_TREE_SIZE + 1);
-
- if (unc_len > MAX_TREE_SIZE)
- return ERR_PTR(-EINVAL);
-
- full_path = kmalloc(unc_len + pplen + 1, GFP_KERNEL);
- if (full_path == NULL)
- return ERR_PTR(-ENOMEM);
-
- memcpy(full_path, ctx->UNC, unc_len);
- pos = full_path + unc_len;
-
- if (pplen) {
- *pos = CIFS_DIR_SEP(cifs_sb);
- memcpy(pos + 1, ctx->prepath, pplen);
- pos += pplen;
- }
-
- *pos = '\0'; /* add trailing null */
- convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
- cifs_dbg(FYI, "%s: full_path=%s\n", __func__, full_path);
- return full_path;
-}
-
static int get_session(struct cifs_mount_ctx *mnt_ctx, const char *full_path)
{
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
@@ -179,6 +146,7 @@ static int __dfs_mount_share(struct cifs
struct TCP_Server_Info *server;
struct cifs_tcon *tcon;
char *origin_fullpath = NULL;
+ char sep = CIFS_DIR_SEP(cifs_sb);
int num_links = 0;
int rc;
@@ -186,7 +154,7 @@ static int __dfs_mount_share(struct cifs
if (IS_ERR(ref_path))
return PTR_ERR(ref_path);
- full_path = build_unc_path_to_root(ctx, cifs_sb, true);
+ full_path = smb3_fs_context_fullpath(ctx, sep);
if (IS_ERR(full_path)) {
rc = PTR_ERR(full_path);
full_path = NULL;
@@ -228,7 +196,7 @@ static int __dfs_mount_share(struct cifs
kfree(full_path);
ref_path = full_path = NULL;
- full_path = build_unc_path_to_root(ctx, cifs_sb, true);
+ full_path = smb3_fs_context_fullpath(ctx, sep);
if (IS_ERR(full_path)) {
rc = PTR_ERR(full_path);
full_path = NULL;
--- a/fs/smb/client/fs_context.c
+++ b/fs/smb/client/fs_context.c
@@ -441,14 +441,17 @@ out:
* but there are some bugs that prevent rename from working if there are
* multiple delimiters.
*
- * Returns a sanitized duplicate of @path. @gfp indicates the GFP_* flags
- * for kstrdup.
+ * Return a sanitized duplicate of @path or NULL for empty prefix paths.
+ * Otherwise, return ERR_PTR.
+ *
+ * @gfp indicates the GFP_* flags for kstrdup.
* The caller is responsible for freeing the original.
*/
#define IS_DELIM(c) ((c) == '/' || (c) == '\\')
char *cifs_sanitize_prepath(char *prepath, gfp_t gfp)
{
char *cursor1 = prepath, *cursor2 = prepath;
+ char *s;
/* skip all prepended delimiters */
while (IS_DELIM(*cursor1))
@@ -469,8 +472,39 @@ char *cifs_sanitize_prepath(char *prepat
if (IS_DELIM(*(cursor2 - 1)))
cursor2--;
- *(cursor2) = '\0';
- return kstrdup(prepath, gfp);
+ *cursor2 = '\0';
+ if (!*prepath)
+ return NULL;
+ s = kstrdup(prepath, gfp);
+ if (!s)
+ return ERR_PTR(-ENOMEM);
+ return s;
+}
+
+/*
+ * Return full path based on the values of @ctx->{UNC,prepath}.
+ *
+ * It is assumed that both values were already parsed by smb3_parse_devname().
+ */
+char *smb3_fs_context_fullpath(const struct smb3_fs_context *ctx, char dirsep)
+{
+ size_t ulen, plen;
+ char *s;
+
+ ulen = strlen(ctx->UNC);
+ plen = ctx->prepath ? strlen(ctx->prepath) + 1 : 0;
+
+ s = kmalloc(ulen + plen + 1, GFP_KERNEL);
+ if (!s)
+ return ERR_PTR(-ENOMEM);
+ memcpy(s, ctx->UNC, ulen);
+ if (plen) {
+ s[ulen] = dirsep;
+ memcpy(s + ulen + 1, ctx->prepath, plen);
+ }
+ s[ulen + plen] = '\0';
+ convert_delimiter(s, dirsep);
+ return s;
}
/*
@@ -484,6 +518,7 @@ smb3_parse_devname(const char *devname,
char *pos;
const char *delims = "/\\";
size_t len;
+ int rc;
if (unlikely(!devname || !*devname)) {
cifs_dbg(VFS, "Device name not specified\n");
@@ -511,6 +546,8 @@ smb3_parse_devname(const char *devname,
/* now go until next delimiter or end of string */
len = strcspn(pos, delims);
+ if (!len)
+ return -EINVAL;
/* move "pos" up to delimiter or NULL */
pos += len;
@@ -533,8 +570,11 @@ smb3_parse_devname(const char *devname,
return 0;
ctx->prepath = cifs_sanitize_prepath(pos, GFP_KERNEL);
- if (!ctx->prepath)
- return -ENOMEM;
+ if (IS_ERR(ctx->prepath)) {
+ rc = PTR_ERR(ctx->prepath);
+ ctx->prepath = NULL;
+ return rc;
+ }
return 0;
}
@@ -1146,12 +1186,13 @@ static int smb3_fs_context_parse_param(s
cifs_errorf(fc, "Unknown error parsing devname\n");
goto cifs_parse_mount_err;
}
- ctx->source = kstrdup(param->string, GFP_KERNEL);
- if (ctx->source == NULL) {
+ ctx->source = smb3_fs_context_fullpath(ctx, '/');
+ if (IS_ERR(ctx->source)) {
+ ctx->source = NULL;
cifs_errorf(fc, "OOM when copying UNC string\n");
goto cifs_parse_mount_err;
}
- fc->source = kstrdup(param->string, GFP_KERNEL);
+ fc->source = kstrdup(ctx->source, GFP_KERNEL);
if (fc->source == NULL) {
cifs_errorf(fc, "OOM when copying UNC string\n");
goto cifs_parse_mount_err;
--- a/fs/smb/client/misc.c
+++ b/fs/smb/client/misc.c
@@ -1211,16 +1211,21 @@ int match_target_ip(struct TCP_Server_In
int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix)
{
+ int rc;
+
kfree(cifs_sb->prepath);
+ cifs_sb->prepath = NULL;
if (prefix && *prefix) {
cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC);
- if (!cifs_sb->prepath)
- return -ENOMEM;
-
- convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb));
- } else
- cifs_sb->prepath = NULL;
+ if (IS_ERR(cifs_sb->prepath)) {
+ rc = PTR_ERR(cifs_sb->prepath);
+ cifs_sb->prepath = NULL;
+ return rc;
+ }
+ if (cifs_sb->prepath)
+ convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb));
+ }
cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
return 0;
