Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932704AbaKRPMG (ORCPT ); Tue, 18 Nov 2014 10:12:06 -0500 Received: from cantor2.suse.de ([195.135.220.15]:57203 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754765AbaKROJe (ORCPT ); Tue, 18 Nov 2014 09:09:34 -0500 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Artem Bityutskiy , Jiri Slaby Subject: [PATCH 3.12 064/206] UBIFS: fix free log space calculation Date: Tue, 18 Nov 2014 15:06:59 +0100 Message-Id: <4f111bbc16e4d6c657c8f53f50d7a9cfa7f37e4f.1416319692.git.jslaby@suse.cz> X-Mailer: git-send-email 2.1.3 In-Reply-To: <28f04bcc068a44c5641c727883947960fb8dcbd5.1416319692.git.jslaby@suse.cz> References: <28f04bcc068a44c5641c727883947960fb8dcbd5.1416319692.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Artem Bityutskiy 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit ba29e721eb2df6df8f33c1f248388bb037a47914 upstream. Hu (hujianyang ) discovered an issue in the 'empty_log_bytes()' function, which calculates how many bytes are left in the log: " If 'c->lhead_lnum + 1 == c->ltail_lnum' and 'c->lhead_offs == c->leb_size', 'h' would equalent to 't' and 'empty_log_bytes()' would return 'c->log_bytes' instead of 0. " At this point it is not clear what would be the consequences of this, and whether this may lead to any problems, but this patch addresses the issue just in case. Tested-by: hujianyang Reported-by: hujianyang Signed-off-by: Artem Bityutskiy Signed-off-by: Jiri Slaby --- fs/ubifs/log.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/ubifs/log.c b/fs/ubifs/log.c index be67120fb919..06649d21b056 100644 --- a/fs/ubifs/log.c +++ b/fs/ubifs/log.c @@ -106,10 +106,14 @@ static inline long long empty_log_bytes(const struct ubifs_info *c) h = (long long)c->lhead_lnum * c->leb_size + c->lhead_offs; t = (long long)c->ltail_lnum * c->leb_size; - if (h >= t) + if (h > t) return c->log_bytes - h + t; - else + else if (h != t) return t - h; + else if (c->lhead_lnum != c->ltail_lnum) + return 0; + else + return c->log_bytes; } /** -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/