Module: wine Branch: master Commit: 44fbc018eda12bdee5c2c1e2e40dbdc6a81b27fd URL: http://source.winehq.org/git/wine.git/?a=commit;h=44fbc018eda12bdee5c2c1e2e4...
Author: Sebastian Lackner sebastian@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" );