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| author | Mitchell Horne <mhorne@FreeBSD.org> | 2023-02-06 18:04:21 +0000 |
|---|---|---|
| committer | Mitchell Horne <mhorne@FreeBSD.org> | 2023-02-15 16:41:39 +0000 |
| commit | 698af78e78093aed0b84f1e5d396e127ae13f52c (patch) | |
| tree | 770fff69a5102e00ed90c1324092d041a8a0bc2e | |
| parent | 2f0fc9ab8912d3446ba67ed28bc7f6d226b16144 (diff) | |
| download | src-698af78e78093aed0b84f1e5d396e127ae13f52c.tar.gz src-698af78e78093aed0b84f1e5d396e127ae13f52c.zip | |
dtrace_asm.S: properly enter/exit user access
In order to read or write userspace memory without generating an access
fault, we must first enable the SUM bit in the sstatus CSR.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38298
(cherry picked from commit 0e563bde48b1af6bd472e940f04a8d76315749ab)
| -rw-r--r-- | sys/cddl/dev/dtrace/riscv/dtrace_asm.S | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/sys/cddl/dev/dtrace/riscv/dtrace_asm.S b/sys/cddl/dev/dtrace/riscv/dtrace_asm.S index eeaf64061675..98c22a2aedfd 100644 --- a/sys/cddl/dev/dtrace/riscv/dtrace_asm.S +++ b/sys/cddl/dev/dtrace/riscv/dtrace_asm.S @@ -74,7 +74,9 @@ uint8_t dtrace_fuword8_nocheck(void *addr) */ ENTRY(dtrace_fuword8_nocheck) + ENTER_USER_ACCESS(t0) lb a0, 0(a0) + EXIT_USER_ACCESS(t0) RET END(dtrace_fuword8_nocheck) @@ -83,7 +85,9 @@ uint16_t dtrace_fuword16_nocheck(void *addr) */ ENTRY(dtrace_fuword16_nocheck) + ENTER_USER_ACCESS(t0) lh a0, 0(a0) + EXIT_USER_ACCESS(t0) RET END(dtrace_fuword16_nocheck) @@ -92,7 +96,9 @@ uint32_t dtrace_fuword32_nocheck(void *addr) */ ENTRY(dtrace_fuword32_nocheck) + ENTER_USER_ACCESS(t0) lw a0, 0(a0) + EXIT_USER_ACCESS(t0) RET END(dtrace_fuword32_nocheck) @@ -101,7 +107,9 @@ uint64_t dtrace_fuword64_nocheck(void *addr) */ ENTRY(dtrace_fuword64_nocheck) + ENTER_USER_ACCESS(t0) ld a0, 0(a0) + EXIT_USER_ACCESS(t0) RET END(dtrace_fuword64_nocheck) @@ -111,6 +119,7 @@ dtrace_copy(uintptr_t uaddr, uintptr_t kaddr, size_t size) */ ENTRY(dtrace_copy) beqz a2, 2f /* If len == 0 then skip loop */ + ENTER_USER_ACCESS(t0) 1: lb a4, 0(a0) /* Load from uaddr */ addi a0, a0, 1 @@ -118,6 +127,7 @@ ENTRY(dtrace_copy) addi a1, a1, 1 addi a2, a2, -1 /* len-- */ bnez a2, 1b + EXIT_USER_ACCESS(t0) 2: RET END(dtrace_copy) @@ -129,7 +139,9 @@ dtrace_copystr(uintptr_t uaddr, uintptr_t kaddr, size_t size, XXX: Check for flags? */ ENTRY(dtrace_copystr) - beqz a2, 2f /* If len == 0 then skip loop */ + beqz a2, 3f /* If len == 0 then skip loop */ + ENTER_USER_ACCESS(t0) +1: lb a4, 0(a0) /* Load from uaddr */ addi a0, a0, 1 sb a4, 0(a1) /* Store in kaddr */ @@ -138,6 +150,8 @@ ENTRY(dtrace_copystr) addi a2, a2, -1 /* len-- */ bnez a2, 1b 2: + EXIT_USER_ACCESS(t0) +3: RET END(dtrace_copystr) |