diff options
author | Eric Sandeen <sandeen@redhat.com> | 2021-07-13 17:49:23 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-20 16:22:44 +0200 |
commit | 3533e50cbee8ff086bfa04176ac42a01ee3db37d (patch) | |
tree | 60089ef2b5327ce776936c21630de6f9926c0891 /fs | |
parent | c41c926d9dfb3c81da370faf678eb06f7f48ba77 (diff) |
seq_file: disallow extremely large seq buffer allocations
commit 8cae8cd89f05f6de223d63e6d15e31c8ba9cf53b upstream.
There is no reasonable need for a buffer larger than this, and it avoids
int overflow pitfalls.
Fixes: 058504edd026 ("fs/seq_file: fallback to vmalloc allocation")
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/seq_file.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/seq_file.c b/fs/seq_file.c index 6dc4296eed62..95e730506ad2 100644 --- a/fs/seq_file.c +++ b/fs/seq_file.c @@ -14,6 +14,7 @@ #include <linux/mm.h> #include <linux/printk.h> #include <linux/string_helpers.h> +#include <linux/pagemap.h> #include <asm/uaccess.h> #include <asm/page.h> @@ -28,6 +29,9 @@ static void *seq_buf_alloc(unsigned long size) void *buf; gfp_t gfp = GFP_KERNEL; + if (unlikely(size > MAX_RW_COUNT)) + return NULL; + /* * For high order allocations, use __GFP_NORETRY to avoid oom-killing - * it's better to fall back to vmalloc() than to kill things. For small |