From: Jean Delvare Subject: [PATCH] Fix misuses of bdevname() Date: Fri, 9 May 2008 13:20:14 +0200 Message-ID: <20080509132014.3379ae2f@hyperion.delvare> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit To: linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, Stephen Tweedie , Andrew Morton , Jens Axboe Return-path: Received: from zone0.gcu-squad.org ([212.85.147.21]:40709 "EHLO services.gcu-squad.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750937AbYEILU0 (ORCPT ); Fri, 9 May 2008 07:20:26 -0400 Sender: linux-ext4-owner@vger.kernel.org List-ID: bdevname() fills the buffer that it is given as a parameter, so calling strcpy() or snprintf() on the returned value is redundant (and probably not guaranteed to work - I don't think strcpy and snprintf support overlapping buffers.) Signed-off-by: Jean Delvare Cc: Stephen Tweedie Cc: Andrew Morton Cc: Jens Axboe --- block/blktrace.c | 2 +- block/compat_ioctl.c | 2 +- fs/ext4/mballoc.c | 6 ++---- fs/jbd2/journal.c | 4 ++-- 4 files changed, 6 insertions(+), 8 deletions(-) --- linux-2.6.26-rc1.orig/block/blktrace.c 2008-05-09 12:52:51.000000000 +0200 +++ linux-2.6.26-rc1/block/blktrace.c 2008-05-09 12:55:04.000000000 +0200 @@ -476,7 +476,7 @@ int blk_trace_ioctl(struct block_device switch (cmd) { case BLKTRACESETUP: - strcpy(b, bdevname(bdev, b)); + bdevname(bdev, b); ret = blk_trace_setup(q, b, bdev->bd_dev, arg); break; case BLKTRACESTART: --- linux-2.6.26-rc1.orig/block/compat_ioctl.c 2008-05-09 12:52:51.000000000 +0200 +++ linux-2.6.26-rc1/block/compat_ioctl.c 2008-05-09 12:55:04.000000000 +0200 @@ -555,7 +555,7 @@ static int compat_blk_trace_setup(struct if (copy_from_user(&cbuts, arg, sizeof(cbuts))) return -EFAULT; - strcpy(b, bdevname(bdev, b)); + bdevname(bdev, b); buts = (struct blk_user_trace_setup) { .act_mask = cbuts.act_mask, --- linux-2.6.26-rc1.orig/fs/ext4/mballoc.c 2008-05-09 12:52:51.000000000 +0200 +++ linux-2.6.26-rc1/fs/ext4/mballoc.c 2008-05-09 12:55:04.000000000 +0200 @@ -2639,8 +2639,7 @@ static int ext4_mb_init_per_dev_proc(str struct proc_dir_entry *proc; char devname[64]; - snprintf(devname, sizeof(devname) - 1, "%s", - bdevname(sb->s_bdev, devname)); + bdevname(sb->s_bdev, devname); sbi->s_mb_proc = proc_mkdir(devname, proc_root_ext4); MB_PROC_HANDLER(EXT4_MB_STATS_NAME, stats); @@ -2674,8 +2673,7 @@ static int ext4_mb_destroy_per_dev_proc( if (sbi->s_mb_proc == NULL) return -EINVAL; - snprintf(devname, sizeof(devname) - 1, "%s", - bdevname(sb->s_bdev, devname)); + bdevname(sb->s_bdev, devname); remove_proc_entry(EXT4_MB_GROUP_PREALLOC, sbi->s_mb_proc); remove_proc_entry(EXT4_MB_STREAM_REQ, sbi->s_mb_proc); remove_proc_entry(EXT4_MB_ORDER2_REQ, sbi->s_mb_proc); --- linux-2.6.26-rc1.orig/fs/jbd2/journal.c 2008-05-09 12:52:51.000000000 +0200 +++ linux-2.6.26-rc1/fs/jbd2/journal.c 2008-05-09 12:55:04.000000000 +0200 @@ -901,7 +901,7 @@ static void jbd2_stats_proc_init(journal { char name[BDEVNAME_SIZE]; - snprintf(name, sizeof(name) - 1, "%s", bdevname(journal->j_dev, name)); + bdevname(journal->j_dev, name); journal->j_proc_entry = proc_mkdir(name, proc_jbd2_stats); if (journal->j_proc_entry) { proc_create_data("history", S_IRUGO, journal->j_proc_entry, @@ -915,7 +915,7 @@ static void jbd2_stats_proc_exit(journal { char name[BDEVNAME_SIZE]; - snprintf(name, sizeof(name) - 1, "%s", bdevname(journal->j_dev, name)); + bdevname(journal->j_dev, name); remove_proc_entry("info", journal->j_proc_entry); remove_proc_entry("history", journal->j_proc_entry); remove_proc_entry(name, proc_jbd2_stats); -- Jean Delvare