Commit e2bb80d5 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

y2038: elfcore: Use __kernel_old_timeval for process times 



We store elapsed time for a crashed process in struct elf_prstatus using
'timeval' structures. Once glibc starts using 64-bit time_t, this becomes
incompatible with the kernel's idea of timeval since the structure layout
no longer matches on 32-bit architectures.

This changes the definition of the elf_prstatus structure to use
__kernel_old_timeval instead, which is hardcoded to the currently used
binary layout. There is no risk of overflow in y2038 though, because
the time values are all relative times, and can store up to 68 years
of process elapsed time.

There is a risk of applications breaking at build time when they
use the new kernel headers and expect the type to be exactly 'timeval'
rather than a structure that has the same fields as before. Those
applications have to be modified to deal with 64-bit time_t anyway.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parent 693737b6

arch/mips/kernel/binfmt_elfn32.c

+2 −2
Original line number Diff line number Diff line
@@ -100,7 +100,7 @@ jiffies_to_old_timeval32(unsigned long jiffies, struct old_timeval32 *value) 
#undef TASK_SIZE

#define TASK_SIZE TASK_SIZE32



#undef ns_to_timeval

#define ns_to_timeval ns_to_old_timeval32

#undef ns_to_kernel_old_timeval

#define ns_to_kernel_old_timeval ns_to_old_timeval32



#include "../../../fs/binfmt_elf.c"

arch/mips/kernel/binfmt_elfo32.c

+2 −2
Original line number Diff line number Diff line
@@ -103,7 +103,7 @@ jiffies_to_old_timeval32(unsigned long jiffies, struct old_timeval32 *value) 
#undef TASK_SIZE

#define TASK_SIZE TASK_SIZE32



#undef ns_to_timeval

#define ns_to_timeval ns_to_old_timeval32

#undef ns_to_kernel_old_timeval

#define ns_to_kernel_old_timeval ns_to_old_timeval32



#include "../../../fs/binfmt_elf.c"

fs/binfmt_elf.c

+6 −6
Original line number Diff line number Diff line
@@ -1489,18 +1489,18 @@ static void fill_prstatus(struct elf_prstatus *prstatus, 
		 * group-wide total, not its individual thread total.

		 */

		thread_group_cputime(p, &cputime);

		prstatus->pr_utime = ns_to_timeval(cputime.utime);

		prstatus->pr_stime = ns_to_timeval(cputime.stime);

		prstatus->pr_utime = ns_to_kernel_old_timeval(cputime.utime);

		prstatus->pr_stime = ns_to_kernel_old_timeval(cputime.stime);

	} else {

		u64 utime, stime;



		task_cputime(p, &utime, &stime);

		prstatus->pr_utime = ns_to_timeval(utime);

		prstatus->pr_stime = ns_to_timeval(stime);

		prstatus->pr_utime = ns_to_kernel_old_timeval(utime);

		prstatus->pr_stime = ns_to_kernel_old_timeval(stime);

	}



	prstatus->pr_cutime = ns_to_timeval(p->signal->cutime);

	prstatus->pr_cstime = ns_to_timeval(p->signal->cstime);

	prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime);

	prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime);

}



static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,

fs/binfmt_elf_fdpic.c

+6 −6
Original line number Diff line number Diff line
@@ -1359,17 +1359,17 @@ static void fill_prstatus(struct elf_prstatus *prstatus, 
		 * group-wide total, not its individual thread total.

		 */

		thread_group_cputime(p, &cputime);

		prstatus->pr_utime = ns_to_timeval(cputime.utime);

		prstatus->pr_stime = ns_to_timeval(cputime.stime);

		prstatus->pr_utime = ns_to_kernel_old_timeval(cputime.utime);

		prstatus->pr_stime = ns_to_kernel_old_timeval(cputime.stime);

	} else {

		u64 utime, stime;



		task_cputime(p, &utime, &stime);

		prstatus->pr_utime = ns_to_timeval(utime);

		prstatus->pr_stime = ns_to_timeval(stime);

		prstatus->pr_utime = ns_to_kernel_old_timeval(utime);

		prstatus->pr_stime = ns_to_kernel_old_timeval(stime);

	}

	prstatus->pr_cutime = ns_to_timeval(p->signal->cutime);

	prstatus->pr_cstime = ns_to_timeval(p->signal->cstime);

	prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime);

	prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime);



	prstatus->pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap;

	prstatus->pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap;

fs/compat_binfmt_elf.c

+2 −2
Original line number Diff line number Diff line
@@ -48,8 +48,8 @@ 
#define elf_prstatus	compat_elf_prstatus

#define elf_prpsinfo	compat_elf_prpsinfo



#undef ns_to_timeval

#define ns_to_timeval ns_to_old_timeval32

#undef ns_to_kernel_old_timeval

#define ns_to_kernel_old_timeval ns_to_old_timeval32



/*

 * To use this file, asm/elf.h must define compat_elf_check_arch.