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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?3RH8yLhoqPtpnePEDYfvb3IasbFre639OstCMINaatt1qNbpv/Co9y7CSDoH?= =?us-ascii?Q?PJFnquCYJYp/KsstXEAiH7Qvr+XZyOdV2Rgz3wcrwYKyecb72NpGJIL84Xys?= =?us-ascii?Q?THwxeU8h3JnauMUeQJ02TTJeqsig9+siH5dw/Y/ZtTTm22qYcMe+ycRqCi/t?= =?us-ascii?Q?XAnJMFOfjGAjnepBKyzcmKp8KiHsNP82E7pXWR6tE3eIsVbl1Jt/0rumWjf4?= =?us-ascii?Q?VeVnV0DuJrnOWgEsVefW+mtMbGKRgUZPu4ag8+ilOAtO99xnuYf9p4PSh4f2?= =?us-ascii?Q?wgkbix8Sl+fAG+VqkYzzXfQDeCjuY3SNrnQ1LSoku3LaOHvFoVy6qQetNgmq?= =?us-ascii?Q?5ym9KHj188YNN9oI0gDymFbXLEjmrGa8sq92c2zxwdMKItI/Gp/RXBcXgaAa?= =?us-ascii?Q?MbspDkEr+eC1wITZXoYNyc0RP6J9ZY7qzxvwe6dMF0IouShMV2Oi3K3ZLdmb?= =?us-ascii?Q?MjErgzgQPeJhlFq/+f3VuaHeSiSslwDVvx5GrTW4LJgQujToM2+P5t0R3GjV?= =?us-ascii?Q?PbxMEFdcPqJXVXIcLHQe3NtgR4eldr1wUVga/uwomNGyIdU6xzQvdUNnzXxp?= =?us-ascii?Q?QyjiGeY0B2au56VNg8Kmox66iX8uSTpnHHeMtKZ5aADCvnD6EoVzGCWRcEL1?= =?us-ascii?Q?Gx2Bxn/OZqzyG2d75eyNd8rnRiA3Lc4nYrmX/IUg941jOjIkD54EUQSpdz6G?= =?us-ascii?Q?bd0/AAdaTterYt5ky3I4uJ0AHXNOWA4+EZ2rq4I8z93gr+vtdJ15Fd3ucy0X?= =?us-ascii?Q?WvwWb+CAQio0fBcsgbaf/qfAQiMWWrMKFVUlswA3Lhf++aafD3oH/2/GDAS+?= =?us-ascii?Q?XMVewiTTjODTt9nb9OSGqgXpo1dtNWPtePSLooqrgf+JprpbZ9cZ0S93SH8C?= =?us-ascii?Q?4eu2gtDQMRxQc12izh24chbR0TGVrLSowOl7C1T7I/Dv9yVMQ2Awno3zCqV3?= =?us-ascii?Q?/Y/pD90wbwkJ1VkZQYyhyEQBQ9EUQ7IG4jCXTeZmdZuS35Y+tbjmdla7oeIA?= =?us-ascii?Q?HXeQdTc2Zskn+63Vaq6zJdAKI4OpJ2B6h13f4IApef/wN4+RY/H1jpuF2sNz?= =?us-ascii?Q?npYyhSGShjqfFAEa9AWpocWzQa6/2nTOcBRRa+mRNHq/H0tXhLcBaSMtRoX9?= =?us-ascii?Q?zTn0Bq+xSChv+mvCRk4U6dyI6o6KwRRwxqRDQ+44XlewxfnnY8GNzEAbtVuy?= =?us-ascii?Q?yzp3jo0/ELjlUgXg6CWr4420xh8o9Yqqjnbyayo3Y2WXb82vmGcUVH3IV85z?= =?us-ascii?Q?RO6Pz2KM71k8xXzAujwlYiFr3Oxbvi/pHxpeVSv5+QfOVdTtJHM6/tWWLcCy?= =?us-ascii?Q?0A5/O+NOKbUkJVUMzWwffs+awAsKp/SBM4SKQBm1PirDGmef/Fu85F4Pwg8M?= =?us-ascii?Q?QFamD6IeoCfMk/h6Y0lxv8ZTzo92C2sjaI3uxCVOa/jw7hC5rjBAPuFuk3sI?= =?us-ascii?Q?cYTLYfWbCgr5P0RZQ1jV9oNktns2UjpHJqfMYiqnefxnygxaatElaU3WKX4a?= =?us-ascii?Q?nuoqQRnzLnri5T4nWPXc5H+gmFvDuotMHMUFwMhXjnkNYWD36rnaX5x5gu6N?= =?us-ascii?Q?rBZ3pLAlXnZ57UM8mYMT2CnvUqXiy3T92sAdpGyoonbJvs/ygvEmnOEW5IVC?= =?us-ascii?Q?9B1gldmdldx6Geh8EcY2YHSr9G74v8KWmaEOP6WPSuXttNrhk6XF0RGyRVdc?= =?us-ascii?Q?Q3ullWGlfH9fIcOf/XaGZEb78ScZbLK/mODJs6131DOLLWkwtr2/cG3XQ28q?= =?us-ascii?Q?h0ybXMIEWw=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 197f15d1-c8e5-4116-ca3b-08deff99436f X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Aug 2026 15:31:26.2184 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: aT2Qvnwt+8CZhlM05ApcysE4XUFWXIEU6nc/hvNqkZ63rAFBEzEdIgfVqC2Q7UcP X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW6PR12MB8736 On 21 Aug 2026, at 11:13, David Laight wrote: > On Fri, 21 Aug 2026 10:24:36 -0400 > "Zi Yan" wrote: > >> On Fri Aug 21, 2026 at 4:30 AM EDT, David Laight wrote: >>> On Sun, 16 Aug 2026 13:52:01 -0700 >>> Andrew Morton wrote: >>> >>>> On Sun, 16 Aug 2026 12:25:48 -0700 syzbot wrote: >>>> >>>>> Hello, >>>>> >>>>> syzbot found the following issue on: >>>>> >>>>> HEAD commit: 3d6d817622b0 Merge tag 'scsi-fixes' of git://git.ke= rnel.or.. >>>>> git tree: upstream >>>>> console output: https://syzkaller.appspot.com/x/log.txt?x=3D1592747= 9580000 >>>>> kernel config: https://syzkaller.appspot.com/x/.config?x=3Da59830c= ba91a1981 >>>>> dashboard link: https://syzkaller.appspot.com/bug?extid=3D805630f14= 53e490427fa >>>>> compiler: Debian clang version 22.1.8 (++20260613092233+e80be= da6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 >>>>> >>>>> Unfortunately, I don't have any reproducer for this issue yet. >>>>> >>>>> Downloadable assets: >>>>> disk image (non-bootable): https://storage.googleapis.com/syzbot-as= sets/d900f083ada3/non_bootable_disk-3d6d8176.raw.xz >>>>> vmlinux: https://storage.googleapis.com/syzbot-assets/d19e0514c02a/= vmlinux-3d6d8176.xz >>>>> kernel image: https://storage.googleapis.com/syzbot-assets/f6da7068= 11f4/bzImage-3d6d8176.xz >>>>> >>>>> IMPORTANT: if you fix the issue, please add the following tag to th= e commit: >>>>> Reported-by: syzbot+805630f1453e490427fa@syzkaller.appspotmail.com >>>>> >>>>> gadgetfs: bound to dummy_udc driver >>>>> ------------[ cut here ]------------ >>>>> 1 >>>>> WARNING: mm/page_alloc.c:5280 at __alloc_frozen_pages_noprof+0x2ce/= 0x380 mm/page_alloc.c:5280, CPU#0: syz.0.0/5319 >>>> >>>> Thanks. drivers/usb/gadget is the offender. >>>> >>>> Gemini sums it up well. "ep_write_iter() needs a bounds check prior= to >>>> memory allocation". https://share.gemini.google/5NzjyttO0ULc >>>> >>>> I expect an easy fix would be >>>> >>>> --- a/drivers/usb/gadget/legacy/inode.c~a >>>> +++ a/drivers/usb/gadget/legacy/inode.c >>>> @@ -666,7 +666,7 @@ ep_write_iter(struct kiocb *iocb, struct >>>> return -EBADMSG; >>>> } >>>> >>>> - buf =3D kmalloc(len, GFP_KERNEL); >>>> + buf =3D kmalloc(len, GFP_KERNEL|__GFP_NOWARN); >>>> if (unlikely(!buf)) { >>>> mutex_unlock(&epdata->lock); >>>> return -ENOMEM; >>>> >>>> or do what Gemini said. Me, I'll add some cc's and run away. >>> >>> Should there be a separate flags for 'request too large' and >>> 'no memory available' ? >> >> What flags? Are you suggesting kmalloc should return an ERR_PTR to >> distinguish different error types? > > That would break to much... +Vlastimil and Harry on this. Maybe worth giving it a try. > I was thinking of a GFP_NOWARN_TOOBIG. > > That isn't enough to change the errno though. > But a smaller sanity limit may make sense anyway. Maybe. I am not sure if we want to spend a GFP flag for that. Best Regards, Yan, Zi