From: Haoxiang Li Date: Tue, 23 Jun 2026 01:45:38 +0000 (+0800) Subject: smb: client: Fix next buffer leak in receive_encrypted_standard() X-Git-Tag: v7.2-rc1~24^2~3 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=1c6267a1d5cf4c73b656f8181b310cbbb3e4767b;p=thirdparty%2Flinux.git smb: client: Fix next buffer leak in receive_encrypted_standard() receive_encrypted_standard() allocates next_buffer before checking whether the number of compound PDUs already reached MAX_COMPOUND. If the limit check fails, the function returns immediately and the newly allocated next_buffer is not assigned to server->smallbuf/server->bigbuf, making it leaked. Move the MAX_COMPOUND check before allocating next_buffer. Fixes: b24df3e30cbf ("cifs: update receive_encrypted_standard to handle compounded responses") Cc: stable@vger.kernel.org Signed-off-by: Haoxiang Li Signed-off-by: Steve French --- diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c index 2964f461fc847..c862a98e52df6 100644 --- a/fs/smb/client/smb2ops.c +++ b/fs/smb/client/smb2ops.c @@ -5111,6 +5111,12 @@ receive_encrypted_standard(struct TCP_Server_Info *server, one_more: shdr = (struct smb2_hdr *)buf; next_cmd = le32_to_cpu(shdr->NextCommand); + + if (*num_mids >= MAX_COMPOUND) { + cifs_server_dbg(VFS, "too many PDUs in compound\n"); + return -1; + } + if (next_cmd) { if (WARN_ON_ONCE(next_cmd > pdu_length)) return -1; @@ -5134,10 +5140,6 @@ one_more: mid_entry->resp_buf_size = server->pdu_size; } - if (*num_mids >= MAX_COMPOUND) { - cifs_server_dbg(VFS, "too many PDUs in compound\n"); - return -1; - } bufs[*num_mids] = buf; mids[(*num_mids)++] = mid_entry;