summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDan Carpenter <dan.carpenter@linaro.org>2024-11-14 11:59:32 +0300
committerAndrew Morton <akpm@linux-foundation.org>2024-11-14 22:43:48 -0800
commit669b0cb81e4e4e78cff77a5b367c7f70c0c6c05e (patch)
treed4dd283a7330b0a37d9a447f25fbba0d0bd330f5
parentfd7b4f9f46d46acbc7af3a439bb0d869efdc5c58 (diff)
fs/proc/task_mmu: prevent integer overflow in pagemap_scan_get_args()
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.mountain 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>
-rw-r--r--fs/proc/task_mmu.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index e52bd96137a6..7eb010de39fe 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -2665,8 +2665,10 @@ static int pagemap_scan_get_args(struct pm_scan_arg *arg,
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 */