diff mbox series

binfmt_flat: Fix integer overflow bug on 32 bit systems

Message ID 5be17f6c-5338-43be-91ef-650153b975cb@stanley.mountain (mailing list archive)
State New
Headers show
Series binfmt_flat: Fix integer overflow bug on 32 bit systems | expand

Commit Message

Dan Carpenter Dec. 4, 2024, 12:07 p.m. UTC 
Most of these sizes and counts are capped at 256MB so the math doesn't
result in an integer overflow.  The "relocs" count needs to be checked
as well.  Otherwise on 32bit systems the calculation of "full_data"
could be wrong.

	full_data = data_len + relocs * sizeof(unsigned long);

Fixes: c995ee28d29d ("binfmt_flat: prevent kernel dammage from corrupted executable headers")
Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 fs/binfmt_flat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 390808ce935d..b5b5ca1a44f7 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -478,7 +478,7 @@  static int load_flat_file(struct linux_binprm *bprm,
 	 * 28 bits (256 MB) is way more than reasonable in this case.
 	 * If some top bits are set we have probable binary corruption.
 	*/
-	if ((text_len | data_len | bss_len | stack_len | full_data) >> 28) {
+	if ((text_len | data_len | bss_len | stack_len | relocs | full_data) >> 28) {
 		pr_err("bad header\n");
 		ret = -ENOEXEC;
 		goto err;