diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c index b63ec7ab6e51..4c8b1b9ade8b 100644 --- a/fs/smb/client/fs_context.c +++ b/fs/smb/client/fs_context.c @@ -736,7 +736,7 @@ static int smb3_fs_context_parse_param(struct fs_context *fc, static int smb3_fs_context_parse_monolithic(struct fs_context *fc, void *data); static int smb3_get_tree(struct fs_context *fc); -static void smb3_sync_ses_chan_max(struct cifs_ses *ses, unsigned int max_channels); +static void smb3_sync_ses_chan_max(struct cifs_ses *ses, size_t max_channels); static int smb3_reconfigure(struct fs_context *fc); static const struct fs_context_operations smb3_fs_context_ops = { @@ -1010,25 +1010,34 @@ do { \ int smb3_sync_session_ctx_passwords(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses) { + char *password = NULL, *password2 = NULL; + if (ses->password && cifs_sb->ctx->password && strcmp(ses->password, cifs_sb->ctx->password)) { - kfree_sensitive(cifs_sb->ctx->password); - cifs_sb->ctx->password = kstrdup(ses->password, GFP_KERNEL); - if (!cifs_sb->ctx->password) + password = kstrdup(ses->password, GFP_KERNEL); + if (!password) return -ENOMEM; } if (ses->password2 && cifs_sb->ctx->password2 && strcmp(ses->password2, cifs_sb->ctx->password2)) { - kfree_sensitive(cifs_sb->ctx->password2); - cifs_sb->ctx->password2 = kstrdup(ses->password2, GFP_KERNEL); - if (!cifs_sb->ctx->password2) { - kfree_sensitive(cifs_sb->ctx->password); - cifs_sb->ctx->password = NULL; + password2 = kstrdup(ses->password2, GFP_KERNEL); + if (!password2) { + kfree_sensitive(password); return -ENOMEM; } } + + if (password) { + kfree_sensitive(cifs_sb->ctx->password); + cifs_sb->ctx->password = password; + } + if (password2) { + kfree_sensitive(cifs_sb->ctx->password2); + cifs_sb->ctx->password2 = password2; + } + return 0; } @@ -1041,7 +1050,7 @@ int smb3_sync_session_ctx_passwords(struct cifs_sb_info *cifs_sb, struct cifs_se * with the session's channel lock. This should be called whenever the maximum * allowed channels for a session changes (e.g., after a remount or reconfigure). */ -static void smb3_sync_ses_chan_max(struct cifs_ses *ses, unsigned int max_channels) +static void smb3_sync_ses_chan_max(struct cifs_ses *ses, size_t max_channels) { spin_lock(&ses->chan_lock); ses->chan_max = max_channels; @@ -1051,12 +1060,15 @@ static void smb3_sync_ses_chan_max(struct cifs_ses *ses, unsigned int max_channe static int smb3_reconfigure(struct fs_context *fc) { struct smb3_fs_context *ctx = smb3_fc2context(fc); + struct smb3_fs_context *new_ctx = NULL; + struct smb3_fs_context *old_ctx = NULL; struct dentry *root = fc->root; struct cifs_sb_info *cifs_sb = CIFS_SB(root->d_sb); struct cifs_ses *ses = cifs_sb_master_tcon(cifs_sb)->ses; unsigned int rsize = ctx->rsize, wsize = ctx->wsize; char *new_password = NULL, *new_password2 = NULL; bool need_recon = false; + bool need_mchan_update; int rc; if (ses->expired_pwd) @@ -1066,6 +1078,16 @@ static int smb3_reconfigure(struct fs_context *fc) if (rc) return rc; + old_ctx = kzalloc_obj(*old_ctx); + if (!old_ctx) + return -ENOMEM; + + rc = smb3_fs_context_dup(old_ctx, cifs_sb->ctx); + if (rc) { + kfree(old_ctx); + return rc; + } + /* * We can not change UNC/username/password/domainname/ * workstation_name/nodename/iocharset @@ -1075,16 +1097,22 @@ static int smb3_reconfigure(struct fs_context *fc) STEAL_STRING(cifs_sb, ctx, UNC); STEAL_STRING(cifs_sb, ctx, source); STEAL_STRING(cifs_sb, ctx, username); + STEAL_STRING(cifs_sb, ctx, domainname); + STEAL_STRING(cifs_sb, ctx, nodename); + STEAL_STRING(cifs_sb, ctx, iocharset); - if (need_recon == false) + if (!need_recon) { STEAL_STRING_SENSITIVE(cifs_sb, ctx, password); - else { + } else { if (ctx->password) { new_password = kstrdup(ctx->password, GFP_KERNEL); - if (!new_password) - return -ENOMEM; - } else + if (!new_password) { + rc = -ENOMEM; + goto restore_ctx; + } + } else { STEAL_STRING_SENSITIVE(cifs_sb, ctx, password); + } } /* @@ -1094,11 +1122,29 @@ static int smb3_reconfigure(struct fs_context *fc) if (ctx->password2) { new_password2 = kstrdup(ctx->password2, GFP_KERNEL); if (!new_password2) { - kfree_sensitive(new_password); - return -ENOMEM; + rc = -ENOMEM; + goto restore_ctx; } - } else + } else { STEAL_STRING_SENSITIVE(cifs_sb, ctx, password2); + } + + /* if rsize or wsize not passed in on remount, use previous values */ + ctx->rsize = rsize ? CIFS_ALIGN_RSIZE(fc, rsize) : cifs_sb->ctx->rsize; + ctx->wsize = wsize ? CIFS_ALIGN_WSIZE(fc, wsize) : cifs_sb->ctx->wsize; + + new_ctx = kzalloc_obj(*new_ctx); + if (!new_ctx) { + rc = -ENOMEM; + goto restore_ctx; + } + + rc = smb3_fs_context_dup(new_ctx, ctx); + if (rc) + goto restore_ctx; + + need_mchan_update = ctx->multichannel != cifs_sb->ctx->multichannel || + ctx->max_channels != cifs_sb->ctx->max_channels; /* * we may update the passwords in the ses struct below. Make sure we do @@ -1109,54 +1155,55 @@ static int smb3_reconfigure(struct fs_context *fc) /* * smb2_reconnect may swap password and password2 in case session setup * failed. First get ctx passwords in sync with ses passwords. It should - * be okay to do this even if this function were to return an error at a - * later stage + * be done before committing new passwords. */ rc = smb3_sync_session_ctx_passwords(cifs_sb, ses); if (rc) { mutex_unlock(&ses->session_mutex); - kfree_sensitive(new_password); - kfree_sensitive(new_password2); - return rc; - } - - /* - * now that allocations for passwords are done, commit them - */ - if (new_password) { - kfree_sensitive(ses->password); - ses->password = new_password; - } - if (new_password2) { - kfree_sensitive(ses->password2); - ses->password2 = new_password2; + goto cleanup_new_ctx; } /* * If multichannel or max_channels has changed, update the session's channels accordingly. * This may add or remove channels to match the new configuration. */ - if ((ctx->multichannel != cifs_sb->ctx->multichannel) || - (ctx->max_channels != cifs_sb->ctx->max_channels)) { - - /* Synchronize ses->chan_max with the new mount context */ - smb3_sync_ses_chan_max(ses, ctx->max_channels); - /* Now update the session's channels to match the new configuration */ + if (need_mchan_update) { /* Prevent concurrent scaling operations */ spin_lock(&ses->ses_lock); if (ses->flags & CIFS_SES_FLAG_SCALE_CHANNELS) { spin_unlock(&ses->ses_lock); mutex_unlock(&ses->session_mutex); - return -EINVAL; + rc = -EINVAL; + goto cleanup_new_ctx; } ses->flags |= CIFS_SES_FLAG_SCALE_CHANNELS; spin_unlock(&ses->ses_lock); + } + + /* + * Commit session passwords before any channel work so newly added + * channels authenticate with the new credentials. + */ + if (new_password) { + kfree_sensitive(ses->password); + ses->password = new_password; + new_password = NULL; + } + if (new_password2) { + kfree_sensitive(ses->password2); + ses->password2 = new_password2; + new_password2 = NULL; + } + + if (need_mchan_update) { + /* Synchronize ses->chan_max with the new mount context */ + smb3_sync_ses_chan_max(ses, ctx->max_channels); mutex_unlock(&ses->session_mutex); - rc = smb3_update_ses_channels(ses, ses->server, - false /* from_reconnect */, - false /* disable_mchan */); + smb3_update_ses_channels(ses, ses->server, + false /* from_reconnect */, + false /* disable_mchan */); /* Clear scaling flag after operation */ spin_lock(&ses->ses_lock); @@ -1166,22 +1213,30 @@ static int smb3_reconfigure(struct fs_context *fc) mutex_unlock(&ses->session_mutex); } - STEAL_STRING(cifs_sb, ctx, domainname); - STEAL_STRING(cifs_sb, ctx, nodename); - STEAL_STRING(cifs_sb, ctx, iocharset); - - /* if rsize or wsize not passed in on remount, use previous values */ - ctx->rsize = rsize ? CIFS_ALIGN_RSIZE(fc, rsize) : cifs_sb->ctx->rsize; - ctx->wsize = wsize ? CIFS_ALIGN_WSIZE(fc, wsize) : cifs_sb->ctx->wsize; - smb3_cleanup_fs_context_contents(cifs_sb->ctx); - rc = smb3_fs_context_dup(cifs_sb->ctx, ctx); + memcpy(cifs_sb->ctx, new_ctx, sizeof(*new_ctx)); + kfree(new_ctx); + new_ctx = NULL; + smb3_cleanup_fs_context(old_ctx); + old_ctx = NULL; smb3_update_mnt_flags(cifs_sb); #ifdef CONFIG_CIFS_DFS_UPCALL if (!rc) rc = dfs_cache_remount_fs(cifs_sb); #endif + return rc; + +cleanup_new_ctx: + smb3_cleanup_fs_context_contents(new_ctx); +restore_ctx: + kfree(new_ctx); + kfree_sensitive(new_password); + kfree_sensitive(new_password2); + smb3_cleanup_fs_context_contents(cifs_sb->ctx); + memcpy(cifs_sb->ctx, old_ctx, sizeof(*old_ctx)); + kfree(old_ctx); + return rc; }