c5c07c5958
This is another instance of incorrect use of list iterator and
checking it for NULL.
The list iterator value 'map' will *always* be set and non-NULL
by list_for_each_entry(), so it is incorrect to assume that the
iterator value will be NULL if the list is empty (in this case, the
check 'if (!map) {' will always be false and never exit as expected).
To fix the bug, use a new variable 'iter' as the list iterator,
while use the original variable 'map' as a dedicated pointer to
point to the found element.
Without this patch, Kernel crashes with below trace:
Unable to handle kernel access to user memory outside uaccess routines
at virtual address 0000ffff7fb03750
...
Call trace:
fastrpc_map_create+0x70/0x290 [fastrpc]
fastrpc_req_mem_map+0xf0/0x2dc [fastrpc]
fastrpc_device_ioctl+0x138/0xc60 [fastrpc]
__arm64_sys_ioctl+0xa8/0xec
invoke_syscall+0x48/0x114
el0_svc_common.constprop.0+0xd4/0xfc
do_el0_svc+0x28/0x90
el0_svc+0x3c/0x130
el0t_64_sync_handler+0xa4/0x130
el0t_64_sync+0x18c/0x190
Code: 14000016 f94000a5 eb05029f 54000260 (b94018a6)
---[ end trace 0000000000000000 ]---
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.