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| author | Jakub Kicinski <kuba@kernel.org> | 2024-03-28 17:24:10 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-03-28 17:25:57 -0700 |
| commit | 5e47fbe5cefe5d25d1fa4481c1b9fbe602b4a69f (patch) | |
| tree | b86edc39098cca1d0e53e46dceec6ca856183642 /arch/riscv/kernel/traps.c | |
| parent | Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf... (diff) | |
| parent | Merge tag 'net-6.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netd... (diff) | |
| download | linux-5e47fbe5cefe5d25d1fa4481c1b9fbe602b4a69f.tar.gz linux-5e47fbe5cefe5d25d1fa4481c1b9fbe602b4a69f.zip | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.
No conflicts, or adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'arch/riscv/kernel/traps.c')
| -rw-r--r-- | arch/riscv/kernel/traps.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index a1b9be3c4332..868d6280cf66 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -6,6 +6,7 @@ #include <linux/cpu.h> #include <linux/kernel.h> #include <linux/init.h> +#include <linux/randomize_kstack.h> #include <linux/sched.h> #include <linux/sched/debug.h> #include <linux/sched/signal.h> @@ -310,7 +311,8 @@ asmlinkage __visible __trap_section void do_trap_break(struct pt_regs *regs) } } -asmlinkage __visible __trap_section void do_trap_ecall_u(struct pt_regs *regs) +asmlinkage __visible __trap_section __no_stack_protector +void do_trap_ecall_u(struct pt_regs *regs) { if (user_mode(regs)) { long syscall = regs->a7; @@ -322,10 +324,23 @@ asmlinkage __visible __trap_section void do_trap_ecall_u(struct pt_regs *regs) syscall = syscall_enter_from_user_mode(regs, syscall); + add_random_kstack_offset(); + if (syscall >= 0 && syscall < NR_syscalls) syscall_handler(regs, syscall); else if (syscall != -1) regs->a0 = -ENOSYS; + /* + * Ultimately, this value will get limited by KSTACK_OFFSET_MAX(), + * so the maximum stack offset is 1k bytes (10 bits). + * + * The actual entropy will be further reduced by the compiler when + * applying stack alignment constraints: 16-byte (i.e. 4-bit) aligned + * for RV32I or RV64I. + * + * The resulting 6 bits of entropy is seen in SP[9:4]. + */ + choose_random_kstack_offset(get_random_u16()); syscall_exit_to_user_mode(regs); } else { |