Greg Kroah-Hartman
598cf27219
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com> Tested-by: Peter Schneider <pschneider1968@googlemail.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Tested-by: Brett A C Sheffield <bacs@librecast.net> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Luna Jernberg <droidbittin@gmail.com> Tested-by: Ronald Warsow <rwarsow@gmx.de> Tested-by: Justin M. Forbes <jforbes@fedoraproject.org> Tested-by: Ron Economos <re@w6rz.net> Tested-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
47 lines
1.2 KiB
C
47 lines
1.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/err.h>
|
|
#include <linux/mm.h>
|
|
#include <asm/current.h>
|
|
#include <asm/traps.h>
|
|
#include <asm/vdso.h>
|
|
|
|
struct vdso_exception_table_entry {
|
|
int insn, fixup;
|
|
};
|
|
|
|
bool fixup_vdso_exception(struct pt_regs *regs, int trapnr,
|
|
unsigned long error_code, unsigned long fault_addr)
|
|
{
|
|
const struct vdso_image *image = current->mm->context.vdso_image;
|
|
const struct vdso_exception_table_entry *extable;
|
|
unsigned int nr_entries, i;
|
|
unsigned long base;
|
|
|
|
/*
|
|
* Do not attempt to fixup #DB or #BP. It's impossible to identify
|
|
* whether or not a #DB/#BP originated from within an SGX enclave and
|
|
* SGX enclaves are currently the only use case for vDSO fixup.
|
|
*/
|
|
if (trapnr == X86_TRAP_DB || trapnr == X86_TRAP_BP)
|
|
return false;
|
|
|
|
if (!current->mm->context.vdso)
|
|
return false;
|
|
|
|
base = (unsigned long)current->mm->context.vdso + image->extable_base;
|
|
nr_entries = image->extable_len / (sizeof(*extable));
|
|
extable = image->extable;
|
|
|
|
for (i = 0; i < nr_entries; i++) {
|
|
if (regs->ip == base + extable[i].insn) {
|
|
regs->ip = base + extable[i].fixup;
|
|
regs->di = trapnr;
|
|
regs->si = error_code;
|
|
regs->dx = fault_addr;
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|