From 6976c7a69dafbb34a0d4814e2def9d3d7114836d Mon Sep 17 00:00:00 2001 From: Wang Zhaolong Date: Fri, 29 Aug 2025 08:59:59 +0800 Subject: smb: client: Fix NULL pointer dereference in cifs_debug_dirs_proc_show() Reading /proc/fs/cifs/open_dirs may hit a NULL dereference when tcon->cfids is NULL. Add NULL check before accessing cfids to prevent the crash. Reproduction: - Mount CIFS share - cat /proc/fs/cifs/open_dirs Fixes: 844e5c0eb176 ("smb3 client: add way to show directory leases for improved debugging") Signed-off-by: Wang Zhaolong Signed-off-by: Steve French --- fs/smb/client/cifs_debug.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/smb/client/cifs_debug.c') diff --git a/fs/smb/client/cifs_debug.c b/fs/smb/client/cifs_debug.c index beb4f18f05ef..edb2e7f7fc23 100644 --- a/fs/smb/client/cifs_debug.c +++ b/fs/smb/client/cifs_debug.c @@ -304,6 +304,8 @@ static int cifs_debug_dirs_proc_show(struct seq_file *m, void *v) list_for_each(tmp1, &ses->tcon_list) { tcon = list_entry(tmp1, struct cifs_tcon, tcon_list); cfids = tcon->cfids; + if (!cfids) + continue; spin_lock(&cfids->cfid_list_lock); /* check lock ordering */ seq_printf(m, "Num entries: %d\n", cfids->num_entries); list_for_each_entry(cfid, &cfids->entries, entry) { @@ -319,8 +321,6 @@ static int cifs_debug_dirs_proc_show(struct seq_file *m, void *v) seq_printf(m, "\n"); } spin_unlock(&cfids->cfid_list_lock); - - } } } -- cgit v1.2.3 From 91be128b496c0de60a7dceb70d34935a29d38bbd Mon Sep 17 00:00:00 2001 From: Bharath SM Date: Tue, 2 Sep 2025 15:28:57 +0530 Subject: smb: client: show negotiated cipher in DebugData Print the negotiated encryption cipher type in DebugData Signed-off-by: Bharath SM Acked-by: Paulo Alcantara (Red Hat) Signed-off-by: Steve French --- fs/smb/client/cifs_debug.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) (limited to 'fs/smb/client/cifs_debug.c') diff --git a/fs/smb/client/cifs_debug.c b/fs/smb/client/cifs_debug.c index edb2e7f7fc23..2337cf795db3 100644 --- a/fs/smb/client/cifs_debug.c +++ b/fs/smb/client/cifs_debug.c @@ -347,6 +347,22 @@ static __always_inline const char *compression_alg_str(__le16 alg) } } +static __always_inline const char *cipher_alg_str(__le16 cipher) +{ + switch (cipher) { + case SMB2_ENCRYPTION_AES128_CCM: + return "AES128-CCM"; + case SMB2_ENCRYPTION_AES128_GCM: + return "AES128-GCM"; + case SMB2_ENCRYPTION_AES256_CCM: + return "AES256-CCM"; + case SMB2_ENCRYPTION_AES256_GCM: + return "AES256-GCM"; + default: + return "UNKNOWN"; + } +} + static int cifs_debug_data_proc_show(struct seq_file *m, void *v) { struct mid_q_entry *mid_entry; @@ -539,6 +555,11 @@ skip_rdma: else seq_puts(m, "disabled (not supported by this server)"); + /* Show negotiated encryption cipher, even if not required */ + seq_puts(m, "\nEncryption: "); + if (server->cipher_type) + seq_printf(m, "Negotiated cipher (%s)", cipher_alg_str(server->cipher_type)); + seq_printf(m, "\n\n\tSessions: "); i = 0; list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) { @@ -576,12 +597,8 @@ skip_rdma: /* dump session id helpful for use with network trace */ seq_printf(m, " SessionId: 0x%llx", ses->Suid); - if (ses->session_flags & SMB2_SESSION_FLAG_ENCRYPT_DATA) { + if (ses->session_flags & SMB2_SESSION_FLAG_ENCRYPT_DATA) seq_puts(m, " encrypted"); - /* can help in debugging to show encryption type */ - if (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM) - seq_puts(m, "(gcm256)"); - } if (ses->sign) seq_puts(m, " signed"); -- cgit v1.2.3