From 5f43086bb9224987010460dcf3dee68fbd4f574d Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sat, 8 Oct 2016 10:12:28 +0200 Subject: [PATCH] locking, fs/locks: Add missing file_sem locks I overlooked a few code-paths that can lead to locks_delete_global_locks(). Reported-by: Dmitry Vyukov Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Jeff Layton Cc: Al Viro Cc: Bruce Fields Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-fsdevel@vger.kernel.org Cc: syzkaller Link: http://lkml.kernel.org/r/20161008081228.GF3142@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar --- fs/locks.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/locks.c b/fs/locks.c index ce93b416b490..22c5b4aa4961 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1609,6 +1609,7 @@ int fcntl_getlease(struct file *filp) ctx = smp_load_acquire(&inode->i_flctx); if (ctx && !list_empty_careful(&ctx->flc_lease)) { + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); time_out_leases(inode, &dispose); list_for_each_entry(fl, &ctx->flc_lease, fl_list) { @@ -1618,6 +1619,8 @@ int fcntl_getlease(struct file *filp) break; } spin_unlock(&ctx->flc_lock); + percpu_up_read_preempt_enable(&file_rwsem); + locks_dispose_list(&dispose); } return type; @@ -2529,11 +2532,14 @@ locks_remove_lease(struct file *filp, struct file_lock_context *ctx) if (list_empty(&ctx->flc_lease)) return; + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); list_for_each_entry_safe(fl, tmp, &ctx->flc_lease, fl_list) if (filp == fl->fl_file) lease_modify(fl, F_UNLCK, &dispose); spin_unlock(&ctx->flc_lock); + percpu_up_read_preempt_enable(&file_rwsem); + locks_dispose_list(&dispose); } -- 2.20.1