{"id":"CVE-2025-38214","title":"fbdev: Fix fb_set_var to prevent null-ptr-deref in fb_videomode_to_var","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nfbdev: Fix fb_set_var to prevent null-ptr-deref in fb_videomode_to_var\n\nIf fb_add_videomode() in fb_set_var() fails to allocate memory for\nfb_videomode, later it may le…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ee20216f12d9482cd70e44dae5e7fabb38367c71","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < fab201d72fde38d081e2c5d4ad25595c535b7b22","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 1a10d91766eb6ddfd5414e4785611e33a4fe0f9b","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ff0e037241173b574b385bff53d67567b9816db5","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3ca78032a388a0795201792b36e6fc9b6e6e8eed","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b3071bb463ea1e6c686d0dc9638fc940f2f5cf17","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8a3a2887794b2c8e78b3e5d6e3de724527c9f41b","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 05f6e183879d9785a3cdf2f08a498bc31b7a20aa","Linux 2.6.12"],"published":"2025-07-04","updated":"2026-10-15","sourceUpdated":"2026-10-15T01:06:49.281Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-38214","references":[{"url":"https://git.kernel.org/stable/c/ee20216f12d9482cd70e44dae5e7fabb38367c71"},{"url":"https://git.kernel.org/stable/c/fab201d72fde38d081e2c5d4ad25595c535b7b22"},{"url":"https://git.kernel.org/stable/c/1a10d91766eb6ddfd5414e4785611e33a4fe0f9b"},{"url":"https://git.kernel.org/stable/c/ff0e037241173b574b385bff53d67567b9816db5"},{"url":"https://git.kernel.org/stable/c/3ca78032a388a0795201792b36e6fc9b6e6e8eed"},{"url":"https://git.kernel.org/stable/c/b3071bb463ea1e6c686d0dc9638fc940f2f5cf17"},{"url":"https://git.kernel.org/stable/c/8a3a2887794b2c8e78b3e5d6e3de724527c9f41b"},{"url":"https://git.kernel.org/stable/c/05f6e183879d9785a3cdf2f08a498bc31b7a20aa"}],"tags":["cve.org"],"epss":0.00188,"epssPercentile":0.08362,"ingestedAt":"2026-10-15T05:52:46.092Z","slug":"CVE-2025-38214","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nfbdev: Fix fb_set_var to prevent null-ptr-deref in fb_videomode_to_var\n\nIf fb_add_videomode() in fb_set_var() fails to allocate memory for\nfb_videomode, later it may lead to a null-ptr dereference in\nfb_videomode_to_var(), as the fb_info is registered while not having the\nmode in modelist that is expected to be there, i.e. the one that is\ndescribed in fb_info->var.\n\n================================================================\ngeneral protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI\nKASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]\nCPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014\nRIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901\nCall Trace:\n display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929\n fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071\n resize_screen drivers/tty/vt/vt.c:1176 [inline]\n vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263\n fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720\n fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776\n do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128\n fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203\n vfs_ioctl fs/ioctl.c:48 [inline]\n __do_sys_ioctl fs/ioctl.c:753 [inline]\n __se_sys_ioctl fs/ioctl.c:739 [inline]\n __x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739\n do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46\n entry_SYSCALL_64_after_hwframe+0x67/0xd1\n================================================================\n\nThe reason is that fb_info->var is being modified in fb_set_var(), and\nthen fb_videomode_to_var() is called. If it fails to add the mode to\nfb_info->modelist, fb_set_var() returns error, but does not restore the\nold value of fb_info->var. Restore fb_info->var on failure the same way\nit is done earlier in the function.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller.\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ee20216f12d9482cd70e44dae5e7fabb38367c71`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < fab201d72fde38d081e2c5d4ad25595c535b7b22`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 1a10d91766eb6ddfd5414e4785611e33a4fe0f9b`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ff0e037241173b574b385bff53d67567b9816db5`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3ca78032a388a0795201792b36e6fc9b6e6e8eed`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b3071bb463ea1e6c686d0dc9638fc940f2f5cf17`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8a3a2887794b2c8e78b3e5d6e3de724527c9f41b`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 05f6e183879d9785a3cdf2f08a498bc31b7a20aa`\n- `Linux 2.6.12`\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":[]}