Re: [PATCH] usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers()

Jeffin Philip <[email protected]>
Newsgroups org.kernel.vger.linux-usb,org.kernel.vger.linux-kernel,org.kernel.vger.stable
Message-ID <[email protected]>
On Mon, 17 Aug 2026 13:10:27 +0200, Greg KH wrote:
>But that is probably a bad idea, right?  Shouldn't we fix that error
>first?

Thanks for the review. Don't quite understand what I need to fix here
(respectfully), should we harden the buffhds null check to include 
ZERO_SIZE_PTRs too, something like this should suffice?:

diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index 640d3bcb7bf0..98643d53cc7a 100644
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -2747,11 +2747,11 @@ int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
 	struct fsg_buffhd *bh, *buffhds;
 	int i;
  
 	buffhds = kzalloc_objs(*buffhds, n);
-	if (!buffhds)
+	if (ZERO_OR_NULL_PTR(buffhds))
 		return -ENOMEM;
 
 	/* Data buffers cyclic list */

Thanks,
Jeffin.
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