From 71ae18ec690953e9ba7107c7cc44589c2cc0d9f1 Mon Sep 17 00:00:00 2001 From: Blaisorblade Date: Wed, 27 Jul 2005 11:45:18 -0700 Subject: [PATCH] sys_get_thread_area does not clear the returned argument sys_get_thread_area does not memset to 0 its struct user_desc info before copying it to user space... since sizeof(struct user_desc) is 16 while the actual datas which are filled are only 12 bytes + 9 bits (across the bitfields), there is a (small) information leak. Signed-off-by: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/process.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch') diff --git a/arch/i386/kernel/process.c b/arch/i386/kernel/process.c index d949205..e3f362e 100644 --- a/arch/i386/kernel/process.c +++ b/arch/i386/kernel/process.c @@ -917,6 +917,8 @@ asmlinkage int sys_get_thread_area(struct user_desc __user *u_info) if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) return -EINVAL; + memset(&info, 0, sizeof(info)); + desc = current->thread.tls_array + idx - GDT_ENTRY_TLS_MIN; info.entry_number = idx; -- cgit v1.1