6.11-stable review patch. If anyone has any objections, please let me know.
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From: Dan Carpenter dan.carpenter@linaro.org
commit 669b0cb81e4e4e78cff77a5b367c7f70c0c6c05e upstream.
The "arg->vec_len" variable is a u64 that comes from the user at the start of the function. The "arg->vec_len * sizeof(struct page_region))" multiplication can lead to integer wrapping. Use size_mul() to avoid that.
Also the size_add/mul() functions work on unsigned long so for 32bit systems we need to ensure that "arg->vec_len" fits in an unsigned long.
Link: https://lkml.kernel.org/r/39d41335-dd4d-48ed-8a7f-402c57d8ea84@stanley.mount... Fixes: 52526ca7fdb9 ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs") Signed-off-by: Dan Carpenter dan.carpenter@linaro.org Cc: Andrei Vagin avagin@google.com Cc: Andrii Nakryiko andrii@kernel.org Cc: Arnd Bergmann arnd@arndb.de Cc: David Hildenbrand david@redhat.com Cc: Matthew Wilcox willy@infradead.org Cc: Michał Mirosław mirq-linux@rere.qmqm.pl Cc: Muhammad Usama Anjum usama.anjum@collabora.com Cc: Oscar Salvador osalvador@suse.de Cc: Peter Xu peterx@redhat.com Cc: Ryan Roberts ryan.roberts@arm.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/proc/task_mmu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -2672,8 +2672,10 @@ static int pagemap_scan_get_args(struct return -EFAULT; if (!arg->vec && arg->vec_len) return -EINVAL; + if (UINT_MAX == SIZE_MAX && arg->vec_len > SIZE_MAX) + return -EINVAL; if (arg->vec && !access_ok((void __user *)(long)arg->vec, - arg->vec_len * sizeof(struct page_region))) + size_mul(arg->vec_len, sizeof(struct page_region)))) return -EFAULT;
/* Fixup default values */