| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Mon, 28 Apr 2008 10:10:22 +0800 From: Dave Young <hidave.darkstar@...il.com> To: linux-kernel@...r.kernel.org Cc: jens.axboe@...cle.com Subject: [PATCH 2/2] loop : Don't hold the lo_ctl_mutex while fput in loop_clr_fd [Fixing bug 10504] If the bakingfile is a block device file, losetuo -d will trigger lockdep warning of "circular locking dependency". open/release lock order : bdev->bd_mutex ---> lo->lo_ctl_mutex loop_clr_fd lock order : lo->lo_ctl_mutex ---> bdev->bd_mutex (fput) Don't hold the lo_ctl_mutex while fput in loop_clr_fd to fix it. It's safe because all loop device state will be consistent here. Signed-off-by: Dave Young <hidave.darkstar@...il.com> --- drivers/block/loop.c | 5 +++++ 1 file changed, 5 insertions(+) diff -upr linux/drivers/block/loop.c linux.new/drivers/block/loop.c --- linux/drivers/block/loop.c 2008-04-25 10:10:25.000000000 +0800 +++ linux.new/drivers/block/loop.c 2008-04-25 10:10:35.000000000 +0800 @@ -923,7 +923,12 @@ static int loop_clr_fd(struct loop_devic bd_set_size(bdev, 0); mapping_set_gfp_mask(filp->f_mapping, gfp); lo->lo_state = Lo_unbound; + + /* unlock the lo_ctl_mutex to silence lockdep in case + the backingfile is a block device */ + mutex_unlock(&lo->lo_ctl_mutex); fput(filp); + mutex_lock(&lo->lo_ctl_mutex); /* This is safe: open() is still holding a reference. */ module_put(THIS_MODULE); if (max_part > 0) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists