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Mon, 17 Aug 2026 06:02:25 -0700 (PDT) From: Jeffin Philip To: gregkh@linuxfoundation.org Cc: christophe.jaillet@wanadoo.fr, felipe.balbi@linux.intel.com, jeffinphilip14@gmail.com, kees@kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, stable@vger.kernel.org, syzbot+791be35f1fbcc85d06d7@syzkaller.appspotmail.com Subject: Re: [PATCH] usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers() Date: Mon, 17 Aug 2026 18:32:08 +0530 Message-ID: <20260817130208.17219-1-jeffinphilip14@gmail.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <2026081701-glitzy-hush-b284@gregkh> References: <2026081701-glitzy-hush-b284@gregkh> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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.