ghsa-q4cm-jgpj-qg42
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
scsi: scsi_debug: Fix out-of-bound read in resp_readcap16()
The following warning was observed running syzkaller:
[ 3813.830724] sg_write: data in/out 65466/242 bytes for SCSI command 0x9e-- guessing data in; [ 3813.830724] program syz-executor not setting count and/or reply_len properly [ 3813.836956] ================================================================== [ 3813.839465] BUG: KASAN: stack-out-of-bounds in sg_copy_buffer+0x157/0x1e0 [ 3813.841773] Read of size 4096 at addr ffff8883cf80f540 by task syz-executor/1549 [ 3813.846612] Call Trace: [ 3813.846995] dump_stack+0x108/0x15f [ 3813.847524] print_address_description+0xa5/0x372 [ 3813.848243] kasan_report.cold+0x236/0x2a8 [ 3813.849439] check_memory_region+0x240/0x270 [ 3813.850094] memcpy+0x30/0x80 [ 3813.850553] sg_copy_buffer+0x157/0x1e0 [ 3813.853032] sg_copy_from_buffer+0x13/0x20 [ 3813.853660] fill_from_dev_buffer+0x135/0x370 [ 3813.854329] resp_readcap16+0x1ac/0x280 [ 3813.856917] schedule_resp+0x41f/0x1630 [ 3813.858203] scsi_debug_queuecommand+0xb32/0x17e0 [ 3813.862699] scsi_dispatch_cmd+0x330/0x950 [ 3813.863329] scsi_request_fn+0xd8e/0x1710 [ 3813.863946] __blk_run_queue+0x10b/0x230 [ 3813.864544] blk_execute_rq_nowait+0x1d8/0x400 [ 3813.865220] sg_common_write.isra.0+0xe61/0x2420 [ 3813.871637] sg_write+0x6c8/0xef0 [ 3813.878853] __vfs_write+0xe4/0x800 [ 3813.883487] vfs_write+0x17b/0x530 [ 3813.884008] ksys_write+0x103/0x270 [ 3813.886268] __x64_sys_write+0x77/0xc0 [ 3813.886841] do_syscall_64+0x106/0x360 [ 3813.887415] entry_SYSCALL_64_after_hwframe+0x44/0xa9
This issue can be reproduced with the following syzkaller log:
r0 = openat(0xffffffffffffff9c, &(0x7f0000000040)='./file0\x00', 0x26e1, 0x0) r1 = syz_open_procfs(0xffffffffffffffff, &(0x7f0000000000)='fd/3\x00') open_by_handle_at(r1, &(0x7f00000003c0)=ANY=[@ANYRESHEX], 0x602000) r2 = syz_open_dev$sg(&(0x7f0000000000), 0x0, 0x40782) write$binfmt_aout(r2, &(0x7f0000000340)=ANY=[@ANYBLOB="00000000deff000000000000000000000000000000000000000000000000000047f007af9e107a41ec395f1bded7be24277a1501ff6196a83366f4e6362bc0ff2b247f68a972989b094b2da4fb3607fcf611a22dd04310d28c75039d"], 0x126)
In resp_readcap16() we get "int alloc_len" value -1104926854, and then pass the huge arr_len to fill_from_dev_buffer(), but arr is only 32 bytes. This leads to OOB in sg_copy_buffer().
To solve this issue, define alloc_len as u32.
{
"affected": [],
"aliases": [
"CVE-2021-47191"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-04-10T19:15:47Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: scsi_debug: Fix out-of-bound read in resp_readcap16()\n\nThe following warning was observed running syzkaller:\n\n[ 3813.830724] sg_write: data in/out 65466/242 bytes for SCSI command 0x9e-- guessing data in;\n[ 3813.830724] program syz-executor not setting count and/or reply_len properly\n[ 3813.836956] ==================================================================\n[ 3813.839465] BUG: KASAN: stack-out-of-bounds in sg_copy_buffer+0x157/0x1e0\n[ 3813.841773] Read of size 4096 at addr ffff8883cf80f540 by task syz-executor/1549\n[ 3813.846612] Call Trace:\n[ 3813.846995] dump_stack+0x108/0x15f\n[ 3813.847524] print_address_description+0xa5/0x372\n[ 3813.848243] kasan_report.cold+0x236/0x2a8\n[ 3813.849439] check_memory_region+0x240/0x270\n[ 3813.850094] memcpy+0x30/0x80\n[ 3813.850553] sg_copy_buffer+0x157/0x1e0\n[ 3813.853032] sg_copy_from_buffer+0x13/0x20\n[ 3813.853660] fill_from_dev_buffer+0x135/0x370\n[ 3813.854329] resp_readcap16+0x1ac/0x280\n[ 3813.856917] schedule_resp+0x41f/0x1630\n[ 3813.858203] scsi_debug_queuecommand+0xb32/0x17e0\n[ 3813.862699] scsi_dispatch_cmd+0x330/0x950\n[ 3813.863329] scsi_request_fn+0xd8e/0x1710\n[ 3813.863946] __blk_run_queue+0x10b/0x230\n[ 3813.864544] blk_execute_rq_nowait+0x1d8/0x400\n[ 3813.865220] sg_common_write.isra.0+0xe61/0x2420\n[ 3813.871637] sg_write+0x6c8/0xef0\n[ 3813.878853] __vfs_write+0xe4/0x800\n[ 3813.883487] vfs_write+0x17b/0x530\n[ 3813.884008] ksys_write+0x103/0x270\n[ 3813.886268] __x64_sys_write+0x77/0xc0\n[ 3813.886841] do_syscall_64+0x106/0x360\n[ 3813.887415] entry_SYSCALL_64_after_hwframe+0x44/0xa9\n\nThis issue can be reproduced with the following syzkaller log:\n\nr0 = openat(0xffffffffffffff9c, \u0026(0x7f0000000040)=\u0027./file0\\x00\u0027, 0x26e1, 0x0)\nr1 = syz_open_procfs(0xffffffffffffffff, \u0026(0x7f0000000000)=\u0027fd/3\\x00\u0027)\nopen_by_handle_at(r1, \u0026(0x7f00000003c0)=ANY=[@ANYRESHEX], 0x602000)\nr2 = syz_open_dev$sg(\u0026(0x7f0000000000), 0x0, 0x40782)\nwrite$binfmt_aout(r2, \u0026(0x7f0000000340)=ANY=[@ANYBLOB=\"00000000deff000000000000000000000000000000000000000000000000000047f007af9e107a41ec395f1bded7be24277a1501ff6196a83366f4e6362bc0ff2b247f68a972989b094b2da4fb3607fcf611a22dd04310d28c75039d\"], 0x126)\n\nIn resp_readcap16() we get \"int alloc_len\" value -1104926854, and then pass\nthe huge arr_len to fill_from_dev_buffer(), but arr is only 32 bytes. This\nleads to OOB in sg_copy_buffer().\n\nTo solve this issue, define alloc_len as u32.",
"id": "GHSA-q4cm-jgpj-qg42",
"modified": "2024-04-10T21:30:31Z",
"published": "2024-04-10T21:30:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47191"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3e20cb072679bdb47747ccc8bee3233a4cf0765a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4e3ace0051e7e504b55d239daab8789dd89b863c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5b8bed6464ad6653586e30df046185fd816ad999"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
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