cbcvebase.
CVE-2021-46935
published 2024-02-27

CVE-2021-46935: In the Linux kernel, the following vulnerability has been resolved: binder: fix async_free_space accounting for empty parcels In 4.13, commit 74310e06be4d…

PriorityP425medium5.5CVSS 3.1
AVLACLPRLUINSUCHINAN
EPSS
0.23%
13.8th percentile
In the Linux kernel, the following vulnerability has been resolved: binder: fix async_free_space accounting for empty parcels In 4.13, commit 74310e06be4d ("android: binder: Move buffer out of area shared with user space") fixed a kernel structure visibility issue. As part of that patch, sizeof(void *) was used as the buffer size for 0-length data payloads so the driver could detect abusive clients sending 0-length asynchronous transactions to a server by enforcing limits on async_free_size. Unfortunately, on the "free" side, the accounting of async_free_space did not add the sizeof(void *) back. The result was that up to 8-bytes of async_free_space were leaked on every async transaction of 8-bytes or less. These small transactions are uncommon, so this accounting issue has gone undetected for several years. The fix is to use "buffer_size" (the allocated buffer size) instead of "size" (the logical buffer size) when updating the async_free_space during the free operation. These are the same except for this corner case of asynchronous transactions with payloads < 8 bytes.

Affected

17 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.15.15-1 (bookworm)linux 5.15.15-1 (bookworm)
linuxlinux
linuxlinux>= 74310e06be4d74dcf67cd108366710dee5c576d5 < 2d2df539d05205fd83c404d5f2dff48d36f9b4952d2df539d05205fd83c404d5f2dff48d36f9b495
linuxlinux>= 74310e06be4d74dcf67cd108366710dee5c576d5 < 7c7064402609aeb6fb11be1b4ec10673ff17b5937c7064402609aeb6fb11be1b4ec10673ff17b593
linuxlinux>= 74310e06be4d74dcf67cd108366710dee5c576d5 < 103b16a8c51f96d5fe063022869ea906c256e5da103b16a8c51f96d5fe063022869ea906c256e5da
linuxlinux>= 74310e06be4d74dcf67cd108366710dee5c576d5 < 1cb8444f3114f0bb2f6e3bcadcf09aa4a28425d41cb8444f3114f0bb2f6e3bcadcf09aa4a28425d4
linuxlinux>= 74310e06be4d74dcf67cd108366710dee5c576d5 < 17691bada6b2f1d5f1c0f6d28cd9d0727023b0ff17691bada6b2f1d5f1c0f6d28cd9d0727023b0ff
linuxlinux>= 74310e06be4d74dcf67cd108366710dee5c576d5 < cfd0d84ba28c18b531648c9d4a35ecca89ad9901cfd0d84ba28c18b531648c9d4a35ecca89ad9901
linuxlinux_kernel>= 0 < 5.10.92-15.10.92-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 4.14.0 < 4.14.2614.14.261
linuxlinux_kernel>= 4.15.0 < 4.19.2244.19.224
linuxlinux_kernel>= 4.20.0 < 5.4.1705.4.170
linuxlinux_kernel>= 5.11.0 < 5.15.135.15.13
linuxlinux_kernel>= 5.5.0 < 5.10.905.10.90

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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