From b525a7e4445c4702dfc541930747517615c0c72a Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Fri, 29 Sep 2006 02:00:26 -0700 Subject: [PATCH] [PATCH] dquot: add proper locking when using current->signal->tty Dquot passes the tty to tty_write_message without locking Signed-off-by: Jan Kara Cc: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/dquot.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/dquot.c b/fs/dquot.c index 0122a27910..9af789567e 100644 --- a/fs/dquot.c +++ b/fs/dquot.c @@ -834,6 +834,9 @@ static void print_warning(struct dquot *dquot, const char warntype) if (!need_print_warning(dquot) || (flag && test_and_set_bit(flag, &dquot->dq_flags))) return; + mutex_lock(&tty_mutex); + if (!current->signal->tty) + goto out_lock; tty_write_message(current->signal->tty, dquot->dq_sb->s_id); if (warntype == ISOFTWARN || warntype == BSOFTWARN) tty_write_message(current->signal->tty, ": warning, "); @@ -861,6 +864,8 @@ static void print_warning(struct dquot *dquot, const char warntype) break; } tty_write_message(current->signal->tty, msg); +out_lock: + mutex_unlock(&tty_mutex); } static inline void flush_warnings(struct dquot **dquots, char *warntype) -- 2.39.5