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path: root/fs/ksmbd/smbacl.c
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Diffstat (limited to 'fs/ksmbd/smbacl.c')
-rw-r--r--fs/ksmbd/smbacl.c130
1 files changed, 88 insertions, 42 deletions
diff --git a/fs/ksmbd/smbacl.c b/fs/ksmbd/smbacl.c
index 38f23bf981ac..3781bca2c8fc 100644
--- a/fs/ksmbd/smbacl.c
+++ b/fs/ksmbd/smbacl.c
@@ -690,6 +690,7 @@ posix_default_acl:
static void set_ntacl_dacl(struct user_namespace *user_ns,
struct smb_acl *pndacl,
struct smb_acl *nt_dacl,
+ unsigned int aces_size,
const struct smb_sid *pownersid,
const struct smb_sid *pgrpsid,
struct smb_fattr *fattr)
@@ -703,9 +704,19 @@ static void set_ntacl_dacl(struct user_namespace *user_ns,
if (nt_num_aces) {
ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
for (i = 0; i < nt_num_aces; i++) {
- memcpy((char *)pndace + size, ntace, le16_to_cpu(ntace->size));
- size += le16_to_cpu(ntace->size);
- ntace = (struct smb_ace *)((char *)ntace + le16_to_cpu(ntace->size));
+ unsigned short nt_ace_size;
+
+ if (offsetof(struct smb_ace, access_req) > aces_size)
+ break;
+
+ nt_ace_size = le16_to_cpu(ntace->size);
+ if (nt_ace_size > aces_size)
+ break;
+
+ memcpy((char *)pndace + size, ntace, nt_ace_size);
+ size += nt_ace_size;
+ aces_size -= nt_ace_size;
+ ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
num_aces++;
}
}
@@ -878,7 +889,7 @@ int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
/* Convert permission bits from mode to equivalent CIFS ACL */
int build_sec_desc(struct user_namespace *user_ns,
struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
- int addition_info, __u32 *secdesclen,
+ int ppntsd_size, int addition_info, __u32 *secdesclen,
struct smb_fattr *fattr)
{
int rc = 0;
@@ -938,15 +949,25 @@ int build_sec_desc(struct user_namespace *user_ns,
if (!ppntsd) {
set_mode_dacl(user_ns, dacl_ptr, fattr);
- } else if (!ppntsd->dacloffset) {
- goto out;
} else {
struct smb_acl *ppdacl_ptr;
+ unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
+ int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
+
+ if (!dacl_offset ||
+ (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
+ goto out;
+
+ ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
+ ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
+ if (ppdacl_size > ntacl_size ||
+ ppdacl_size < sizeof(struct smb_acl))
+ goto out;
- ppdacl_ptr = (struct smb_acl *)((char *)ppntsd +
- le32_to_cpu(ppntsd->dacloffset));
set_ntacl_dacl(user_ns, dacl_ptr, ppdacl_ptr,
- nowner_sid_ptr, ngroup_sid_ptr, fattr);
+ ntacl_size - sizeof(struct smb_acl),
+ nowner_sid_ptr, ngroup_sid_ptr,
+ fattr);
}
pntsd->dacloffset = cpu_to_le32(offset);
offset += le16_to_cpu(dacl_ptr->size);
@@ -980,24 +1001,31 @@ int smb_inherit_dacl(struct ksmbd_conn *conn,
struct smb_sid owner_sid, group_sid;
struct dentry *parent = path->dentry->d_parent;
struct user_namespace *user_ns = mnt_user_ns(path->mnt);
- int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0;
- int rc = 0, num_aces, dacloffset, pntsd_type, acl_len;
+ int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
+ int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
char *aces_base;
bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
- acl_len = ksmbd_vfs_get_sd_xattr(conn, user_ns,
- parent, &parent_pntsd);
- if (acl_len <= 0)
+ pntsd_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
+ parent, &parent_pntsd);
+ if (pntsd_size <= 0)
return -ENOENT;
dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
- if (!dacloffset) {
+ if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
rc = -EINVAL;
goto free_parent_pntsd;
}
parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
+ acl_len = pntsd_size - dacloffset;
num_aces = le32_to_cpu(parent_pdacl->num_aces);
pntsd_type = le16_to_cpu(parent_pntsd->type);
+ pdacl_size = le16_to_cpu(parent_pdacl->size);
+
+ if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
+ rc = -EINVAL;
+ goto free_parent_pntsd;
+ }
aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
if (!aces_base) {
@@ -1008,11 +1036,23 @@ int smb_inherit_dacl(struct ksmbd_conn *conn,
aces = (struct smb_ace *)aces_base;
parent_aces = (struct smb_ace *)((char *)parent_pdacl +
sizeof(struct smb_acl));
+ aces_size = acl_len - sizeof(struct smb_acl);
if (pntsd_type & DACL_AUTO_INHERITED)
inherited_flags = INHERITED_ACE;
for (i = 0; i < num_aces; i++) {
+ int pace_size;
+
+ if (offsetof(struct smb_ace, access_req) > aces_size)
+ break;
+
+ pace_size = le16_to_cpu(parent_aces->size);
+ if (pace_size > aces_size)
+ break;
+
+ aces_size -= pace_size;
+
flags = parent_aces->flags;
if (!smb_inherit_flags(flags, is_dir))
goto pass;
@@ -1057,8 +1097,7 @@ int smb_inherit_dacl(struct ksmbd_conn *conn,
aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
ace_cnt++;
pass:
- parent_aces =
- (struct smb_ace *)((char *)parent_aces + le16_to_cpu(parent_aces->size));
+ parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
}
if (nt_size > 0) {
@@ -1153,7 +1192,7 @@ int smb_check_perm_dacl(struct ksmbd_conn *conn, struct path *path,
struct smb_ntsd *pntsd = NULL;
struct smb_acl *pdacl;
struct posix_acl *posix_acls;
- int rc = 0, acl_size;
+ int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
struct smb_sid sid;
int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
struct smb_ace *ace;
@@ -1162,37 +1201,33 @@ int smb_check_perm_dacl(struct ksmbd_conn *conn, struct path *path,
struct smb_ace *others_ace = NULL;
struct posix_acl_entry *pa_entry;
unsigned int sid_type = SIDOWNER;
- char *end_of_acl;
+ unsigned short ace_size;
ksmbd_debug(SMB, "check permission using windows acl\n");
- acl_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
- path->dentry, &pntsd);
- if (acl_size <= 0 || !pntsd || !pntsd->dacloffset) {
- kfree(pntsd);
- return 0;
- }
+ pntsd_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
+ path->dentry, &pntsd);
+ if (pntsd_size <= 0 || !pntsd)
+ goto err_out;
+
+ dacl_offset = le32_to_cpu(pntsd->dacloffset);
+ if (!dacl_offset ||
+ (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
+ goto err_out;
pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
- end_of_acl = ((char *)pntsd) + acl_size;
- if (end_of_acl <= (char *)pdacl) {
- kfree(pntsd);
- return 0;
- }
+ acl_size = pntsd_size - dacl_offset;
+ pdacl_size = le16_to_cpu(pdacl->size);
- if (end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size) ||
- le16_to_cpu(pdacl->size) < sizeof(struct smb_acl)) {
- kfree(pntsd);
- return 0;
- }
+ if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
+ goto err_out;
if (!pdacl->num_aces) {
- if (!(le16_to_cpu(pdacl->size) - sizeof(struct smb_acl)) &&
+ if (!(pdacl_size - sizeof(struct smb_acl)) &&
*pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
rc = -EACCES;
goto err_out;
}
- kfree(pntsd);
- return 0;
+ goto err_out;
}
if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
@@ -1200,11 +1235,16 @@ int smb_check_perm_dacl(struct ksmbd_conn *conn, struct path *path,
DELETE;
ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
+ aces_size = acl_size - sizeof(struct smb_acl);
for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
+ if (offsetof(struct smb_ace, access_req) > aces_size)
+ break;
+ ace_size = le16_to_cpu(ace->size);
+ if (ace_size > aces_size)
+ break;
+ aces_size -= ace_size;
granted |= le32_to_cpu(ace->access_req);
ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
- if (end_of_acl < (char *)ace)
- goto err_out;
}
if (!pdacl->num_aces)
@@ -1216,7 +1256,15 @@ int smb_check_perm_dacl(struct ksmbd_conn *conn, struct path *path,
id_to_sid(uid, sid_type, &sid);
ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
+ aces_size = acl_size - sizeof(struct smb_acl);
for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
+ if (offsetof(struct smb_ace, access_req) > aces_size)
+ break;
+ ace_size = le16_to_cpu(ace->size);
+ if (ace_size > aces_size)
+ break;
+ aces_size -= ace_size;
+
if (!compare_sids(&sid, &ace->sid) ||
!compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
found = 1;
@@ -1226,8 +1274,6 @@ int smb_check_perm_dacl(struct ksmbd_conn *conn, struct path *path,
others_ace = ace;
ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
- if (end_of_acl < (char *)ace)
- goto err_out;
}
if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-23 17:15:43 +0000