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author | Dmitry V. Levin <ldv@altlinux.org> | 2019-03-29 20:12:21 +0300 |
---|---|---|
committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-04-04 10:25:31 -0400 |
commit | 10a16997db3d99fc02c026cf2c6e6c670acafab0 (patch) | |
tree | b26a45e42c002f64ac9e34bf648b1b1b0d18ee1b /arch/riscv | |
parent | d08e411397cb6fcb3d3fb075c27a41975c99e88f (diff) | |
download | lwn-10a16997db3d99fc02c026cf2c6e6c670acafab0.tar.gz lwn-10a16997db3d99fc02c026cf2c6e6c670acafab0.zip |
riscv: Fix syscall_get_arguments() and syscall_set_arguments()
RISC-V syscall arguments are located in orig_a0,a1..a5 fields
of struct pt_regs.
Due to an off-by-one bug and a bug in pointer arithmetic
syscall_get_arguments() was reading s3..s7 fields instead of a1..a5.
Likewise, syscall_set_arguments() was writing s3..s7 fields
instead of a1..a5.
Link: http://lkml.kernel.org/r/20190329171221.GA32456@altlinux.org
Fixes: e2c0cdfba7f69 ("RISC-V: User-facing API")
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: linux-riscv@lists.infradead.org
Cc: stable@vger.kernel.org # v4.15+
Acked-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'arch/riscv')
-rw-r--r-- | arch/riscv/include/asm/syscall.h | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/arch/riscv/include/asm/syscall.h b/arch/riscv/include/asm/syscall.h index bba3da6ef157..6ea9e1804233 100644 --- a/arch/riscv/include/asm/syscall.h +++ b/arch/riscv/include/asm/syscall.h @@ -79,10 +79,11 @@ static inline void syscall_get_arguments(struct task_struct *task, if (i == 0) { args[0] = regs->orig_a0; args++; - i++; n--; + } else { + i--; } - memcpy(args, ®s->a1 + i * sizeof(regs->a1), n * sizeof(args[0])); + memcpy(args, ®s->a1 + i, n * sizeof(args[0])); } static inline void syscall_set_arguments(struct task_struct *task, @@ -94,10 +95,11 @@ static inline void syscall_set_arguments(struct task_struct *task, if (i == 0) { regs->orig_a0 = args[0]; args++; - i++; n--; - } - memcpy(®s->a1 + i * sizeof(regs->a1), args, n * sizeof(regs->a0)); + } else { + i--; + } + memcpy(®s->a1 + i, args, n * sizeof(regs->a1)); } static inline int syscall_get_arch(void) |