{"id":"CVE-2026-53304","title":"scsi: sg: Resolve soft lockup issue when opening /dev/sgX","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: sg: Resolve soft lockup issue when opening /dev/sgX\n\nThe parameter def_reserved_size defines the default buffer size reserved\nfor each Sg_fd and should be restric…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < 3d74e0654ac908c65a8f20373091826fe43b1363","Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < c47ccfb3d80dfed522ca06a5954ac97488d78c5a","Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < fe671d3c84ffb1b763d590c25195755adeaadaba","Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < c5f4a211e82d04ccc1809311322c47023bbe66e2","Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < 9676ca7b1ef31a3a65b3e61e7ce3b54ce7364202","Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < 1afd963fcd963db0dc5d47df6dfcf010c9c4647e","Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < feade299e932967de27519338d41de348fb5b061","Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < d06a310b45e153872033dd0cf19d5a2279121099","Linux 2.6.19"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:26:08.178511Z"},"published":"2026-06-26","updated":"2026-11-06","sourceUpdated":"2026-11-06T16:34:19.492Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-53304","references":[{"url":"https://git.kernel.org/stable/c/3d74e0654ac908c65a8f20373091826fe43b1363"},{"url":"https://git.kernel.org/stable/c/c47ccfb3d80dfed522ca06a5954ac97488d78c5a"},{"url":"https://git.kernel.org/stable/c/fe671d3c84ffb1b763d590c25195755adeaadaba"},{"url":"https://git.kernel.org/stable/c/c5f4a211e82d04ccc1809311322c47023bbe66e2"},{"url":"https://git.kernel.org/stable/c/9676ca7b1ef31a3a65b3e61e7ce3b54ce7364202"},{"url":"https://git.kernel.org/stable/c/1afd963fcd963db0dc5d47df6dfcf010c9c4647e"},{"url":"https://git.kernel.org/stable/c/feade299e932967de27519338d41de348fb5b061"},{"url":"https://git.kernel.org/stable/c/d06a310b45e153872033dd0cf19d5a2279121099"}],"tags":["cve.org"],"epss":0.00101,"epssPercentile":0.00885,"ingestedAt":"2026-11-06T16:57:43.249Z","slug":"CVE-2026-53304","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nscsi: sg: Resolve soft lockup issue when opening /dev/sgX\n\nThe parameter def_reserved_size defines the default buffer size reserved\nfor each Sg_fd and should be restricted to a range between 0 and 1,048,576\n(see https://tldp.org/HOWTO/SCSI-Generic-HOWTO/proc.html).  Although the\nfunction sg_proc_write_dressz enforces this limit, it is possible to bypass\nit by directly modifying the module parameter as shown below, which then\ncauses a soft lockup:\n\necho -1 > /sys/module/sg/parameters/def_reserved_size\nexec 4<> /dev/sg0\n\nwatchdog: BUG: soft lockup - CPU#5 stuck for 26 seconds! [bash:537]\nModules loaded:\nCPU: 5 UID: 0 PID: 537 Command: bash, kernel version 6.19.0-rc3+ #134,\nPREEMPT disabled\nHardware: QEMU Standard PC (i440FX + PIIX, 1996), BIOS version\n1.16.1-2.fc37 dated 04/01/2014\n...\nCall Trace:\n\n  sg_build_reserve+0x5c/0xa0\n  sg_add_sfp+0x168/0x270\n  sg_open+0x16e/0x340\n  chrdev_open+0xbe/0x230\n  do_dentry_open+0x175/0x480\n  vfs_open+0x34/0xf0\n  do_open+0x265/0x3d0\n  path_openat+0x110/0x290\n  do_filp_open+0xc3/0x170\n  do_sys_openat2+0x71/0xe0\n  __x64_sys_openat+0x6d/0xa0\n  do_syscall_64+0x62/0x310\n  entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nThe fix is to use module_param_cb to validate and reject invalid values\nassigned to def_reserved_size.\n\n## Affected\n\n- `Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < 3d74e0654ac908c65a8f20373091826fe43b1363`\n- `Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < c47ccfb3d80dfed522ca06a5954ac97488d78c5a`\n- `Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < fe671d3c84ffb1b763d590c25195755adeaadaba`\n- `Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < c5f4a211e82d04ccc1809311322c47023bbe66e2`\n- `Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < 9676ca7b1ef31a3a65b3e61e7ce3b54ce7364202`\n- `Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < 1afd963fcd963db0dc5d47df6dfcf010c9c4647e`\n- `Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < feade299e932967de27519338d41de348fb5b061`\n- `Linux >= 6460e75a104d10458817d2f5b2fbff775bf0b43a < d06a310b45e153872033dd0cf19d5a2279121099`\n- `Linux 2.6.19`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}