diff options
| author | Namjae Jeon <linkinjeon@kernel.org> | 2025-02-12 09:37:57 +0900 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2025-03-02 22:50:54 -0600 |
| commit | aa2a739a75ab6f24ef72fb3fdb9192c081eacf06 (patch) | |
| tree | 7762449cd1dcce60eb17435b672d7f5fa42e43fe /fs/smb/client | |
| parent | 1b8b67f3c5e5169535e26efedd3e422172e2db64 (diff) | |
cifs: fix incorrect validation for num_aces field of smb_acl
parse_dcal() validate num_aces to allocate ace array.
f (num_aces > ULONG_MAX / sizeof(struct smb_ace *))
It is an incorrect validation that we can create an array of size ULONG_MAX.
smb_acl has ->size field to calculate actual number of aces in response buffer
size. Use this to check invalid num_aces.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/smb/client')
| -rw-r--r-- | fs/smb/client/cifsacl.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/smb/client/cifsacl.c b/fs/smb/client/cifsacl.c index 7d953208046a..64bd68f750f8 100644 --- a/fs/smb/client/cifsacl.c +++ b/fs/smb/client/cifsacl.c @@ -778,7 +778,8 @@ static void parse_dacl(struct smb_acl *pdacl, char *end_of_acl, } /* validate that we do not go past end of acl */ - if (end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) { + if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) || + end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) { cifs_dbg(VFS, "ACL too small to parse DACL\n"); return; } @@ -799,8 +800,11 @@ static void parse_dacl(struct smb_acl *pdacl, char *end_of_acl, if (num_aces > 0) { umode_t denied_mode = 0; - if (num_aces > ULONG_MAX / sizeof(struct smb_ace *)) + if (num_aces > (le16_to_cpu(pdacl->size) - sizeof(struct smb_acl)) / + (offsetof(struct smb_ace, sid) + + offsetof(struct smb_sid, sub_auth) + sizeof(__le16))) return; + ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL); if (!ppace) |