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![Maninder Singh](/assets/img/avatar_default.png)
function kallsyms_show_value() is used by other parts like modules_open(), kprobes_read() etc. which can work in case of !KALLSYMS also. e.g. as of now lsmod do not show module address if KALLSYMS is disabled. since kallsyms_show_value() defination is not present, it returns false in !KALLSYMS. / # lsmod test 12288 0 - Live 0x0000000000000000 (O) So kallsyms_show_value() can be made generic without dependency on KALLSYMS. Thus moving out function to a new file ksyms_common.c. With this patch code is just moved to new file and no functional change. Co-developed-by: Onkarnath <onkarnath.1@samsung.com> Signed-off-by: Onkarnath <onkarnath.1@samsung.com> Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Reviewed-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
46 lines
1 KiB
C
46 lines
1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* ksyms_common.c: A split of kernel/kallsyms.c
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* Contains a few generic function definations independent of config KALLSYMS.
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*/
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#include <linux/kallsyms.h>
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#include <linux/security.h>
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#ifdef CONFIG_KALLSYMS
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static inline int kallsyms_for_perf(void)
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{
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#ifdef CONFIG_PERF_EVENTS
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extern int sysctl_perf_event_paranoid;
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if (sysctl_perf_event_paranoid <= 1)
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return 1;
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#endif
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return 0;
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}
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/*
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* We show kallsyms information even to normal users if we've enabled
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* kernel profiling and are explicitly not paranoid (so kptr_restrict
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* is clear, and sysctl_perf_event_paranoid isn't set).
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*
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* Otherwise, require CAP_SYSLOG (assuming kptr_restrict isn't set to
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* block even that).
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*/
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bool kallsyms_show_value(const struct cred *cred)
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{
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switch (kptr_restrict) {
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case 0:
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if (kallsyms_for_perf())
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return true;
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fallthrough;
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case 1:
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if (security_capable(cred, &init_user_ns, CAP_SYSLOG,
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CAP_OPT_NOAUDIT) == 0)
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return true;
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fallthrough;
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default:
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return false;
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}
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}
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#endif
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