The recent introduction of SA_X32/IA32 sa_flags added a check for user_64bit_mode() into sigaction_compat_abi(). user_64bit_mode() is true for native 64-bit processes and x32 processes.
Due to that the function returns w/o setting the SA_X32_ABI flag for X32 processes. In consequence the kernel attempts to deliver the signal to the X32 process in native 64-bit mode causing the process to segfault. Remove the check, so the actual check for X32 mode which sets the ABI flag can be reached. There is no side effect for native 64-bit mode. [ tglx: Rewrote changelog ] Fixes: 6846351052e6 ("x86/signal: Add SA_{X32,IA32}_ABI sa_flags") Reported-by: Mikulas Patocka <mpato...@redhat.com> Tested-by: Adam Borowski <kilob...@angband.pl> Signed-off-by: Dmitry Safonov <0x7f454...@gmail.com> Cc: Dmitry Safonov <dsafo...@virtuozzo.com> Cc: Oleg Nesterov <o...@redhat.com> Cc: linux...@kvack.org Cc: Cyrill Gorcunov <gorcu...@openvz.org> Cc: Pavel Emelyanov <xe...@virtuozzo.com> Link: http://lkml.kernel.org/r/cajwjo6z8zwpqnft6t-i8gw1mkxqrkduagqqnz%2b0%2b697%3dmyv...@mail.gmail.com Signed-off-by: Thomas Gleixner <t...@linutronix.de> Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Dmitry Safonov <dsafo...@virtuozzo.com> [backported from ms commit ed1e7db33c33 ("x86/signal: Remove bogus user_64bit_mode() check from sigaction_compat_abi()")] Signed-off-by: Dmitry Safonov <dsafo...@virtuozzo.com> --- arch/x86/ia32/ia32_signal.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index 9c6c4de8da46..cbd5c5ad5edf 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -47,9 +47,6 @@ void sigaction_compat_abi(struct k_sigaction *act, struct k_sigaction *oact) /* Don't let flags to be set from userspace */ act->sa.sa_flags &= ~(SA_IA32_ABI | SA_X32_ABI); - if (user_64bit_mode(current_pt_regs())) - return; - if (is_ia32_task()) act->sa.sa_flags |= SA_IA32_ABI; if (is_x32_task()) -- 2.10.1 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel