From d8b7418ba4cf2bf2571f66a42517b9bced1b9132 Mon Sep 17 00:00:00 2001 From: Jim Keniston Date: Wed, 11 Mar 2009 14:42:29 -0700 Subject: Don't reject opcode 0x9b -- fwait, which is also the first byte of pseudo-instructions like fclex, finit, fstsw, and fstcw. Do reject opcode 0x82 in 64-bit mode. --- runtime/uprobes/uprobes_x86.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'runtime/uprobes/uprobes_x86.c') diff --git a/runtime/uprobes/uprobes_x86.c b/runtime/uprobes/uprobes_x86.c index e3bdf8ff..404c9518 100644 --- a/runtime/uprobes/uprobes_x86.c +++ b/runtime/uprobes/uprobes_x86.c @@ -45,8 +45,8 @@ static const unsigned long long good_insns_64[256 / 64] = { W(0x50, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 50 */ W(0x60, 0,0,0,1,1,1,0,0,1,1,1,1,0,0,0,0)| /* 60 */ W(0x70, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1), /* 70 */ - W(0x80, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 80 */ - W(0x90, 1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1)| /* 90 */ + W(0x80, 1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 80 */ + W(0x90, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 90 */ W(0xa0, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* a0 */ W(0xb0, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1), /* b0 */ W(0xc0, 1,1,1,1,0,0,1,1,1,1,1,1,0,0,0,0)| /* c0 */ @@ -71,7 +71,7 @@ static const unsigned long long good_insns_32[256 / 64] = { W(0x60, 1,1,1,0,1,1,0,0,1,1,1,1,0,0,0,0)| /* 60 */ W(0x70, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1), /* 70 */ W(0x80, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 80 */ - W(0x90, 1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1)| /* 90 */ + W(0x90, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 90 */ W(0xa0, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* a0 */ W(0xb0, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1), /* b0 */ W(0xc0, 1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0)| /* c0 */ @@ -119,7 +119,7 @@ static const unsigned long long good_2byte_insns[256 / 64] = { * 0f - lar, lsl, syscall, clts, sysret, sysenter, sysexit, invd, wbinvd, ud2 * * invalid opcodes in 64-bit mode: - * 06, 0e, 16, 1e, 27, 2f, 37, 3f, 60-62, c4-c5, d4-d5 + * 06, 0e, 16, 1e, 27, 2f, 37, 3f, 60-62, 82, c4-c5, d4-d5 * * 63 - we support this opcode in x86_64 but not in i386. * opcodes we may need to refine support for: @@ -141,7 +141,6 @@ static const unsigned long long good_2byte_insns[256 / 64] = { * 26, 2e, 36, 3e - es:, cs:, ss:, ds: segment prefixes -- * but 64 and 65 (fs: and gs:) seems to be used, so we support them. * 67 - addr16 prefix - * 9b - wait/fwait * ce - into * f0 - lock prefix */ -- cgit From 436e5bf634020bcb9f98967891508db21f9e6cbd Mon Sep 17 00:00:00 2001 From: Jim Keniston Date: Mon, 20 Apr 2009 16:39:26 -0700 Subject: PR10078: uretprobes on functions returning structs/unions arch_predict_sp_at_ret() for x86_32 now accommodates ret $4. Added bz10078 regression test. --- runtime/uprobes/uprobes_x86.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'runtime/uprobes/uprobes_x86.c') diff --git a/runtime/uprobes/uprobes_x86.c b/runtime/uprobes/uprobes_x86.c index 404c9518..93331715 100644 --- a/runtime/uprobes/uprobes_x86.c +++ b/runtime/uprobes/uprobes_x86.c @@ -716,12 +716,23 @@ unsigned long arch_hijack_uret_addr(unsigned long trampoline_address, return orig_ret_addr; } +/* + * On x86_32, if a function returns a struct or union, the return + * value is copied into an area created by the caller. The address + * of this area is passed on the stack as a "hidden" first argument. + * When such a function returns, it uses a "ret $4" instruction to pop + * not only the return address but also the hidden arg. To accommodate + * such functions, we add 4 bytes of slop when predicting the return + * address. See PR #10078. + */ +#define STRUCT_RETURN_SLOP 4 + static unsigned long arch_predict_sp_at_ret(struct pt_regs *regs, struct task_struct *tsk) { if (test_tsk_thread_flag(tsk, TIF_IA32)) - return (unsigned long) (REGS_SP + 4); + return (unsigned long) (REGS_SP + 4 + STRUCT_RETURN_SLOP); else return (unsigned long) (REGS_SP + 8); } -- cgit