Sebastian Lackner : winebuild: Do not access memory below ESP when restoring thread contexts.
Alexandre Julliard
julliard at wine.codeweavers.com
Fri Feb 27 08:00:16 CST 2015
Module: wine
Branch: master
Commit: 44fbc018eda12bdee5c2c1e2e40dbdc6a81b27fd
URL: http://source.winehq.org/git/wine.git/?a=commit;h=44fbc018eda12bdee5c2c1e2e40dbdc6a81b27fd
Author: Sebastian Lackner <sebastian at fds-team.de>
Date: Thu Feb 12 11:09:34 2015 +0100
winebuild: Do not access memory below ESP when restoring thread contexts.
Based on a patch by John Reiser.
---
tools/winebuild/relay.c | 49 +++++++++++++++++++++++++++++++++----------------
1 file changed, 33 insertions(+), 16 deletions(-)
diff --git a/tools/winebuild/relay.c b/tools/winebuild/relay.c
index cc7dd37..63c2ca4 100644
--- a/tools/winebuild/relay.c
+++ b/tools/winebuild/relay.c
@@ -852,31 +852,48 @@ static void build_call_from_regs_x86(void)
/* Restore the context structure */
- output( "2:\tpushl 0x94(%%ecx)\n"); /* SegEs */
+ output( "2:\n" );
+
+ /* As soon as we have switched stacks the context structure could
+ * be invalid (when signal handlers are executed for example). Copy
+ * values on the target stack before changing ESP. */
+
+ output( "\tpushl 0xc8(%%ecx)\n" ); /* SegSs */
+ output( "\tpopl %%es\n" );
+ output( "\tmovl 0xc4(%%ecx),%%eax\n" ); /* Esp */
+ output( "\tleal -4*4(%%eax),%%eax\n" );
+
+ output( "\tmovl 0xc0(%%ecx),%%edx\n" ); /* EFlags */
+ output( "\t.byte 0x26\n\tmovl %%edx,3*4(%%eax)\n" );
+ output( "\tmovl 0xbc(%%ecx),%%edx\n" ); /* SegCs */
+ output( "\t.byte 0x26\n\tmovl %%edx,2*4(%%eax)\n" );
+ output( "\tmovl 0xb8(%%ecx),%%edx\n" ); /* Eip */
+ output( "\t.byte 0x26\n\tmovl %%edx,1*4(%%eax)\n" );
+ output( "\tmovl 0xb0(%%ecx),%%edx\n" ); /* Eax */
+ output( "\t.byte 0x26\n\tmovl %%edx,0*4(%%eax)\n" );
+
+ output( "\tpushl %%es\n" );
+ output( "\tpushl 0x98(%%ecx)\n" ); /* SegDs */
+
+ output(" \tpushl 0x94(%%ecx)\n" ); /* SegEs */
output( "\tpopl %%es\n" );
output( "\tpushl 0x90(%%ecx)\n"); /* SegFs */
output( "\tpopl %%fs\n" );
output( "\tpushl 0x8c(%%ecx)\n"); /* SegGs */
output( "\tpopl %%gs\n" );
- output( "\tmovl 0x9c(%%ecx),%%edi\n"); /* Edi */
- output( "\tmovl 0xa0(%%ecx),%%esi\n"); /* Esi */
- output( "\tmovl 0xa8(%%ecx),%%edx\n"); /* Edx */
- output( "\tmovl 0xa4(%%ecx),%%ebx\n"); /* Ebx */
- output( "\tmovl 0xb0(%%ecx),%%eax\n"); /* Eax */
- output( "\tmovl 0xb4(%%ecx),%%ebp\n"); /* Ebp */
+ output( "\tmovl 0x9c(%%ecx),%%edi\n" ); /* Edi */
+ output( "\tmovl 0xa0(%%ecx),%%esi\n" ); /* Esi */
+ output( "\tmovl 0xa4(%%ecx),%%ebx\n" ); /* Ebx */
+ output( "\tmovl 0xa8(%%ecx),%%edx\n" ); /* Edx */
+ output( "\tmovl 0xb4(%%ecx),%%ebp\n" ); /* Ebp */
+ output( "\tmovl 0xac(%%ecx),%%ecx\n" ); /* Ecx */
- output( "\tpushl 0xc8(%%ecx)\n"); /* SegSs */
+ output( "\tpopl %%ds\n" );
output( "\tpopl %%ss\n" );
- output( "\tmovl 0xc4(%%ecx),%%esp\n"); /* Esp */
+ output( "\tmovl %%eax,%%esp\n" );
- output( "\tpushl 0xc0(%%ecx)\n"); /* EFlags */
- output( "\tpushl 0xbc(%%ecx)\n"); /* SegCs */
- output( "\tpushl 0xb8(%%ecx)\n"); /* Eip */
- output( "\tpushl 0x98(%%ecx)\n"); /* SegDs */
- output( "\tmovl 0xac(%%ecx),%%ecx\n"); /* Ecx */
-
- output( "\tpopl %%ds\n" );
+ output( "\tpopl %%eax\n" );
output( "\tiret\n" );
output_cfi( ".cfi_endproc" );
output_function_size( "__wine_call_from_regs" );
More information about the wine-cvs
mailing list