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linux-user: Fix broken m68k signal handling on 64 bit hosts

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The m68k signal frame setup code which writes the signal return
trampoline code to the stack was assuming that a 'long' was 32 bits;
on 64 bit systems this meant we would end up writing the 32 bit
(2 insn) trampoline sequence to retaddr+4,retaddr+6 instead of
the intended retaddr+0,retaddr+2, resulting in a guest crash when
it tried to execute the invalid zero-bytes at retaddr+0.
Fix by using uint32_t instead; also use uint16_t rather than short
for consistency. This fixes bug LP:1404690.

Reported-by: Michel Boaventura
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
This commit is contained in:
Peter Maydell 2014-12-22 17:47:00 +00:00 committed by Riku Voipio
parent ec355f1547
commit 1669add752
1 changed files with 3 additions and 3 deletions
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6
linux-user/signal.c
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@ -5066,7 +5066,7 @@ static void setup_frame(int sig, struct target_sigaction *ka,
/* moveq #,d0; trap #0 */ /* moveq #,d0; trap #0 */
__put_user(0x70004e40 + (TARGET_NR_sigreturn << 16), __put_user(0x70004e40 + (TARGET_NR_sigreturn << 16),
(long *)(frame->retcode)); (uint32_t *)(frame->retcode));
/* Set up to return from userspace */ /* Set up to return from userspace */
@ -5200,8 +5200,8 @@ static void setup_rt_frame(int sig, struct target_sigaction *ka,
/* moveq #,d0; notb d0; trap #0 */ /* moveq #,d0; notb d0; trap #0 */
__put_user(0x70004600 + ((TARGET_NR_rt_sigreturn ^ 0xff) << 16), __put_user(0x70004600 + ((TARGET_NR_rt_sigreturn ^ 0xff) << 16),
(long *)(frame->retcode + 0)); (uint32_t *)(frame->retcode + 0));
__put_user(0x4e40, (short *)(frame->retcode + 4)); __put_user(0x4e40, (uint16_t *)(frame->retcode + 4));
if (err) if (err)
goto give_sigsegv; goto give_sigsegv;