[PATCH] alloc_tag: Tighten file permissions on /proc/allocinfo

[Kees Cook]

The /proc/allocinfo file exposes a tremendous about of information about
kernel build details, memory allocations (obviously), and potentially
even image layout (due to ordering). As this is intended to be consumed
by system owners (like /proc/slabinfo), use the same file permissions as
there: 0400.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
---
 lib/alloc_tag.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
index 26af9982ddc4..531dbe2f5456 100644
--- a/lib/alloc_tag.c
+++ b/lib/alloc_tag.c
@@ -129,7 +129,7 @@ size_t alloc_tag_top_users(struct codetag_bytes *tags, size_t count, bool can_sl
 
 static void __init procfs_init(void)
 {
-	proc_create_seq("allocinfo", 0444, NULL, &allocinfo_seq_op);
+	proc_create_seq("allocinfo", 0400, NULL, &allocinfo_seq_op);
 }
 
 static bool alloc_tag_module_unload(struct codetag_type *cttype,
-- 
2.34.1