277f4ddc36
commit b17c2baa305cccbd16bafa289fd743cc2db77966 upstream. Replace all ret/retq instructions with ASM_RET in preparation of making it more than a single instruction. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211204134907.964635458@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 5.10: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
23 lines
492 B
C
23 lines
492 B
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/linkage.h>
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#include <linux/error-injection.h>
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#include <linux/kprobes.h>
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asmlinkage void just_return_func(void);
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asm(
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".text\n"
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".type just_return_func, @function\n"
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".globl just_return_func\n"
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"just_return_func:\n"
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ASM_RET
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".size just_return_func, .-just_return_func\n"
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);
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void override_function_with_return(struct pt_regs *regs)
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{
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regs->ip = (unsigned long)&just_return_func;
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}
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NOKPROBE_SYMBOL(override_function_with_return);
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