c2e1be1448
[ Upstream commit da20ab35180780e4a6eadc804544f1fa967f3567 ] We do not have tracepoints for sys_modify_ldt() because we define it directly instead of using the normal SYSCALL_DEFINEx() macros. However, there is a reason sys_modify_ldt() does not use the macros: it has an 'int' return type instead of 'unsigned long'. This is a bug, but it's a bug cemented in the ABI. What does this mean? If we return -EINVAL from a function that returns 'int', we have 0x00000000ffffffea in %rax. But, if we return -EINVAL from a function returning 'unsigned long', we end up with 0xffffffffffffffea in %rax, which is wrong. To work around this and maintain the 'int' behavior while using the SYSCALL_DEFINEx() macros, so we add a cast to 'unsigned int' in both implementations of sys_modify_ldt(). Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Brian Gerst <brgerst@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20171018172107.1A79C532@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| .. | ||
| asm | ||
| os-Linux | ||
| shared/sysdep | ||
| vdso | ||
| bug.c | ||
| bugs_32.c | ||
| bugs_64.c | ||
| checksum_32.S | ||
| delay.c | ||
| elfcore.c | ||
| fault.c | ||
| Kconfig | ||
| ksyms.c | ||
| ldt.c | ||
| Makefile | ||
| mem_32.c | ||
| mem_64.c | ||
| ptrace_32.c | ||
| ptrace_64.c | ||
| ptrace_user.c | ||
| setjmp_32.S | ||
| setjmp_64.S | ||
| signal.c | ||
| stub_32.S | ||
| stub_64.S | ||
| stub_segv.c | ||
| sys_call_table_32.c | ||
| sys_call_table_64.c | ||
| syscalls_64.c | ||
| sysrq_32.c | ||
| sysrq_64.c | ||
| tls_32.c | ||
| tls_64.c | ||
| user-offsets.c | ||