cbcvebase.
CVE-2023-53487
published 2025-10-01

CVE-2023-53487: In the Linux kernel, the following vulnerability has been resolved: powerpc/rtas_flash: allow user copy to flash block cache objects With hardened usercopy…

PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.15%
5.0th percentile
In the Linux kernel, the following vulnerability has been resolved: powerpc/rtas_flash: allow user copy to flash block cache objects With hardened usercopy enabled (CONFIG_HARDENED_USERCOPY=y), using the /proc/powerpc/rtas/firmware_update interface to prepare a system firmware update yields a BUG(): kernel BUG at mm/usercopy.c:102! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 0 PID: 2232 Comm: dd Not tainted 6.5.0-rc3+ #2 Hardware name: IBM,8408-E8E POWER8E (raw) 0x4b0201 0xf000004 of:IBM,FW860.50 (SV860_146) hv:phyp pSeries NIP: c0000000005991d0 LR: c0000000005991cc CTR: 0000000000000000 REGS: c0000000148c76a0 TRAP: 0700 Not tainted (6.5.0-rc3+) MSR: 8000000000029033 CR: 24002242 XER: 0000000c CFAR: c0000000001fbd34 IRQMASK: 0 [ ... GPRs omitted ... ] NIP usercopy_abort+0xa0/0xb0 LR usercopy_abort+0x9c/0xb0 Call Trace: usercopy_abort+0x9c/0xb0 (unreliable) __check_heap_object+0x1b4/0x1d0 __check_object_size+0x2d0/0x380 rtas_flash_write+0xe4/0x250 proc_reg_write+0xfc/0x160 vfs_write+0xfc/0x4e0 ksys_write+0x90/0x160 system_call_exception+0x178/0x320 system_call_common+0x160/0x2c4 The blocks of the firmware image are copied directly from user memory to objects allocated from flash_block_cache, so flash_block_cache must be created using kmem_cache_create_usercopy() to mark it safe for user access. [mpe: Trim and indent oops]

Affected

20 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.52-1 (bookworm)linux 6.1.52-1 (bookworm)
linuxlinux
linuxlinux>= 6d07d1cd300f4c7e16005f881fea388164999cc8 < 8f09cc15dcd91d16562400c51d24c7be0d5796fa8f09cc15dcd91d16562400c51d24c7be0d5796fa
linuxlinux>= 6d07d1cd300f4c7e16005f881fea388164999cc8 < 1d29e21ed09fa668416fa7721e08d451b99034851d29e21ed09fa668416fa7721e08d451b9903485
linuxlinux>= 6d07d1cd300f4c7e16005f881fea388164999cc8 < 0ba7f969be599e21d4b1f1e947593de6515f49960ba7f969be599e21d4b1f1e947593de6515f4996
linuxlinux>= 6d07d1cd300f4c7e16005f881fea388164999cc8 < 8ef25fb13494e35c6dbe15445c7875fa92bc3e8b8ef25fb13494e35c6dbe15445c7875fa92bc3e8b
linuxlinux>= 6d07d1cd300f4c7e16005f881fea388164999cc8 < b8fee83aa4ed3846c7f50a0b364bc699f48d96e5b8fee83aa4ed3846c7f50a0b364bc699f48d96e5
linuxlinux>= 6d07d1cd300f4c7e16005f881fea388164999cc8 < 6acb8a453388374fafb3c3b37534b675b2aa0ae16acb8a453388374fafb3c3b37534b675b2aa0ae1
linuxlinux>= 6d07d1cd300f4c7e16005f881fea388164999cc8 < 4f3175979e62de3b929bfa54a0db4b87d36257a74f3175979e62de3b929bfa54a0db4b87d36257a7
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.197-15.10.197-1
linuxlinux_kernel>= 0 < 6.1.52-16.1.52-1
linuxlinux_kernel>= 0 < 6.4.13-16.4.13-1
linuxlinux_kernel>= 0 < 6.4.13-16.4.13-1
linuxlinux_kernel>= 4.16 < 4.19.2934.19.293
linuxlinux_kernel>= 4.20 < 5.4.2555.4.255
linuxlinux_kernel>= 5.11 < 5.15.1285.15.128
linuxlinux_kernel>= 5.16 < 6.1.476.1.47
linuxlinux_kernel>= 5.5 < 5.10.1925.10.192
linuxlinux_kernel>= 6.2 < 6.4.126.4.12

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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