diff options
author | Tor Egge <tegge@FreeBSD.org> | 2006-09-26 04:12:49 +0000 |
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committer | Tor Egge <tegge@FreeBSD.org> | 2006-09-26 04:12:49 +0000 |
commit | 5da56ddb21063670827f5b998dbd968005fba920 (patch) | |
tree | ac46e0b5a80f88127d3d14dc940a5f2746573c00 /sys/kern/vfs_syscalls.c | |
parent | b14f05094a39269e312930006275c146d4362e24 (diff) | |
download | src-5da56ddb21063670827f5b998dbd968005fba920.tar.gz src-5da56ddb21063670827f5b998dbd968005fba920.zip |
Use mount interlock to protect all changes to mnt_flag and mnt_kern_flag.
This eliminates a race where MNT_UPDATE flag could be lost when nmount()
raced against sync(), sync_fsync() or quotactl().
Notes
Notes:
svn path=/head/; revision=162647
Diffstat (limited to 'sys/kern/vfs_syscalls.c')
-rw-r--r-- | sys/kern/vfs_syscalls.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c index cbef3505d1e2..147b31e10767 100644 --- a/sys/kern/vfs_syscalls.c +++ b/sys/kern/vfs_syscalls.c @@ -133,11 +133,15 @@ sync(td, uap) vfslocked = VFS_LOCK_GIANT(mp); if ((mp->mnt_flag & MNT_RDONLY) == 0 && vn_start_write(NULL, &mp, V_NOWAIT) == 0) { + MNT_ILOCK(mp); asyncflag = mp->mnt_flag & MNT_ASYNC; mp->mnt_flag &= ~MNT_ASYNC; + MNT_IUNLOCK(mp); vfs_msync(mp, MNT_NOWAIT); VFS_SYNC(mp, MNT_NOWAIT, td); + MNT_ILOCK(mp); mp->mnt_flag |= asyncflag; + MNT_IUNLOCK(mp); vn_finished_write(mp); } VFS_UNLOCK_GIANT(vfslocked); |