From: Chris Wright <[email protected]> commit df09162550fbb53354f0c88e85b5d0e6129ee9cc upstream.
Be sure to avoid entering t_show() with FTRACE_ITER_HASH set without having properly started the iterator to iterate the hash. This case is degenerate and, as discovered by Robert Swiecki, can cause t_hash_show() to misuse a pointer. This causes a NULL ptr deref with possible security implications. Tracked as CVE-2010-3079. Cc: Robert Swiecki <[email protected]> Cc: Eugene Teo <[email protected]> Signed-off-by: Chris Wright <[email protected]> Signed-off-by: Steven Rostedt <[email protected]> Signed-off-by: Paul Gortmaker <[email protected]> --- kernel/trace/ftrace.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 7d51cab..73dedb3 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1488,6 +1488,8 @@ static void *t_start(struct seq_file *m, loff_t *pos) if (*pos > 0) return t_hash_start(m, pos); iter->flags |= FTRACE_ITER_PRINTALL; + /* reset in case of seek/pread */ + iter->flags &= ~FTRACE_ITER_HASH; return iter; } -- 1.7.3.3 _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
