linux.git/arch/x86/kernel/vmlinux.lds.S, branch v3.10 Linux kernel source tree x86: Drop always empty .text..page_aligned section 2013-03-11T14:07:56+00:00 Jan Beulich JBeulich@suse.com 2013-03-11T10:06:12+00:00 ec7fd34425f6536ed4b3548e7aa712ee2718189c Commit e44b7b7 ("x86: move suspend wakeup code to C") didn't care to also eliminate the side effects that the earlier 4c49156 ("x86: make arch/x86/kernel/acpi/wakeup_32.S use a separate") had, thus leaving a now pointless, almost page size gap at the beginning of .text. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Pavel Machek <pavel@ucw.cz> Link: http://lkml.kernel.org/r/513DBAA402000078000C4896@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> 
Commit e44b7b7 ("x86: move suspend wakeup code to C") didn't
care to also eliminate the side effects that the earlier 4c49156
("x86: make arch/x86/kernel/acpi/wakeup_32.S use a separate")
had, thus leaving a now pointless, almost page size gap at the
beginning of .text.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Pavel Machek <pavel@ucw.cz>
Link: http://lkml.kernel.org/r/513DBAA402000078000C4896@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86, realmode: Move ACPI wakeup to unified realmode code 2012-05-08T18:46:05+00:00 Jarkko Sakkinen jarkko.sakkinen@intel.com 2012-05-08T18:22:29+00:00 c9b77ccb52a5c77233b0e557b7d4417b00ef4012 Migrated ACPI wakeup code to the real-mode blob. Code existing in .x86_trampoline can be completely removed. Static descriptor table in wakeup_asm.S is courtesy of H. Peter Anvin. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-7-git-send-email-jarkko.sakkinen@intel.com Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Len Brown <len.brown@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
Migrated ACPI wakeup code to the real-mode blob.
Code existing in .x86_trampoline  can be completely
removed. Static descriptor table in wakeup_asm.S is
courtesy of H. Peter Anvin.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-7-git-send-email-jarkko.sakkinen@intel.com
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <len.brown@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86-64: Rework vsyscall emulation and add vsyscall= parameter 2011-08-11T00:26:46+00:00 Andy Lutomirski luto@mit.edu 2011-08-10T15:15:32+00:00 3ae36655b97a03fa1decf72f04078ef945647c1a There are three choices: vsyscall=native: Vsyscalls are native code that issues the corresponding syscalls. vsyscall=emulate (default): Vsyscalls are emulated by instruction fault traps, tested in the bad_area path. The actual contents of the vsyscall page is the same as the vsyscall=native case except that it's marked NX. This way programs that make assumptions about what the code in the page does will not be confused when they read that code. vsyscall=none: Trying to execute a vsyscall will segfault. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/8449fb3abf89851fd6b2260972666a6f82542284.1312988155.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
There are three choices:

vsyscall=native: Vsyscalls are native code that issues the
corresponding syscalls.

vsyscall=emulate (default): Vsyscalls are emulated by instruction
fault traps, tested in the bad_area path.  The actual contents of
the vsyscall page is the same as the vsyscall=native case except
that it's marked NX.  This way programs that make assumptions about
what the code in the page does will not be confused when they read
that code.

vsyscall=none: Trying to execute a vsyscall will segfault.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/8449fb3abf89851fd6b2260972666a6f82542284.1312988155.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86-64: Work around gold bug 13023 2011-08-04T23:13:38+00:00 Andy Lutomirski luto@MIT.EDU 2011-08-03T13:31:51+00:00 f670bb760e7d32ec9c690e748a1d5d04921363ab Gold has trouble assigning numbers to the location counter inside of an output section description. The bug was triggered by 9fd67b4ed0714ab718f1f9bd14c344af336a6df7, which consolidated all of the vsyscall sections into a single section. The workaround is IMO still nicer than the old way of doing it. This produces an apparently valid kernel image and passes my vdso tests on both GNU ld version 2.21.51.0.6-2.fc15 20110118 and GNU gold (version 2.21.51.0.6-2.fc15 20110118) 1.10 as distributed by Fedora 15. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/0b260cb806f1f9a25c00ce8377a5f035d57f557a.1312378163.git.luto@mit.edu Reported-by: Arkadiusz Miskiewicz <a.miskiewicz@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
Gold has trouble assigning numbers to the location counter inside of
an output section description.  The bug was triggered by
9fd67b4ed0714ab718f1f9bd14c344af336a6df7, which consolidated all of
the vsyscall sections into a single section.  The workaround is IMO
still nicer than the old way of doing it.

This produces an apparently valid kernel image and passes my vdso
tests on both GNU ld version 2.21.51.0.6-2.fc15 20110118 and GNU
gold (version 2.21.51.0.6-2.fc15 20110118) 1.10 as distributed by
Fedora 15.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/0b260cb806f1f9a25c00ce8377a5f035d57f557a.1312378163.git.luto@mit.edu
Reported-by: Arkadiusz Miskiewicz <a.miskiewicz@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86-64: Move the "user" vsyscall segment out of the data segment. 2011-08-04T23:13:35+00:00 Andy Lutomirski luto@MIT.EDU 2011-08-03T13:31:50+00:00 9c40818da5b39fca236029059ab839857b1ef56c The kernel's loader doesn't seem to care, but gold complains. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/f0716870c297242a841b949953d80c0d87bf3d3f.1312378163.git.luto@mit.edu Reported-by: Arkadiusz Miskiewicz <a.miskiewicz@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
The kernel's loader doesn't seem to care, but gold complains.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/f0716870c297242a841b949953d80c0d87bf3d3f.1312378163.git.luto@mit.edu
Reported-by: Arkadiusz Miskiewicz <a.miskiewicz@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86-64: Move vread_tsc and vread_hpet into the vDSO 2011-07-15T00:57:05+00:00 Andy Lutomirski luto@mit.edu 2011-07-14T10:47:22+00:00 98d0ac38ca7b1b7a552c9a2359174ff84decb600 The vsyscall page now consists entirely of trap instructions. Cc: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
The vsyscall page now consists entirely of trap instructions.

Cc: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86-64: Fill unused parts of the vsyscall page with 0xcc 2011-06-06T07:43:14+00:00 Andy Lutomirski luto@MIT.EDU 2011-06-05T17:50:23+00:00 5dfcea629a08b4684a019cd0cb59d0c9129a6c02 Jumping to 0x00 might do something depending on the following bytes. Jumping to 0xcc is a trap. So fill the unused parts of the vsyscall page with 0xcc to make it useless for exploits to jump there. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Jesper Juhl <jj@chaosbits.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Mikael Pettersson <mikpe@it.uu.se> Cc: Andi Kleen <andi@firstfloor.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Louis Rilling <Louis.Rilling@kerlabs.com> Cc: Valdis.Kletnieks@vt.edu Cc: pageexec@freemail.hu Link: http://lkml.kernel.org/r/ed54bfcfbe50a9070d20ec1edbe0d149e22a4568.1307292171.git.luto@mit.edu Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Jumping to 0x00 might do something depending on the following
bytes. Jumping to 0xcc is a trap.  So fill the unused parts of
the vsyscall page with 0xcc to make it useless for exploits to
jump there.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Louis Rilling <Louis.Rilling@kerlabs.com>
Cc: Valdis.Kletnieks@vt.edu
Cc: pageexec@freemail.hu
Link: http://lkml.kernel.org/r/ed54bfcfbe50a9070d20ec1edbe0d149e22a4568.1307292171.git.luto@mit.edu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86-64: Remove vsyscall number 3 (venosys) 2011-06-06T07:43:14+00:00 Andy Lutomirski luto@mit.edu 2011-06-05T17:50:22+00:00 bb5fe2f78eadf5a52d8dcbf9a57728fd107af97b It just segfaults since April 2008 (a4928cff), so I'm pretty sure that nothing uses it. And having an empty section makes the linker script a bit fragile. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Jesper Juhl <jj@chaosbits.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Mikael Pettersson <mikpe@it.uu.se> Cc: Andi Kleen <andi@firstfloor.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Louis Rilling <Louis.Rilling@kerlabs.com> Cc: Valdis.Kletnieks@vt.edu Cc: pageexec@freemail.hu Link: http://lkml.kernel.org/r/4a4abcf47ecadc269f2391a313576fe6d06acef7.1307292171.git.luto@mit.edu Signed-off-by: Ingo Molnar <mingo@elte.hu> 
It just segfaults since April 2008 (a4928cff), so I'm pretty
sure that nothing uses it.  And having an empty section makes
the linker script a bit fragile.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Louis Rilling <Louis.Rilling@kerlabs.com>
Cc: Valdis.Kletnieks@vt.edu
Cc: pageexec@freemail.hu
Link: http://lkml.kernel.org/r/4a4abcf47ecadc269f2391a313576fe6d06acef7.1307292171.git.luto@mit.edu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86-64: Give vvars their own page 2011-06-05T19:30:32+00:00 Andy Lutomirski luto@MIT.EDU 2011-06-05T17:50:19+00:00 9fd67b4ed0714ab718f1f9bd14c344af336a6df7 Move vvars out of the vsyscall page into their own page and mark it NX. Without this patch, an attacker who can force a daemon to call some fixed address could wait until the time contains, say, 0xCD80, and then execute the current time. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Jesper Juhl <jj@chaosbits.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Mikael Pettersson <mikpe@it.uu.se> Cc: Andi Kleen <andi@firstfloor.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Louis Rilling <Louis.Rilling@kerlabs.com> Cc: Valdis.Kletnieks@vt.edu Cc: pageexec@freemail.hu Link: http://lkml.kernel.org/r/b1460f81dc4463d66ea3f2b5ce240f58d48effec.1307292171.git.luto@mit.edu Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Move vvars out of the vsyscall page into their own page and mark
it NX.

Without this patch, an attacker who can force a daemon to call
some fixed address could wait until the time contains, say,
0xCD80, and then execute the current time.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Louis Rilling <Louis.Rilling@kerlabs.com>
Cc: Valdis.Kletnieks@vt.edu
Cc: pageexec@freemail.hu
Link: http://lkml.kernel.org/r/b1460f81dc4463d66ea3f2b5ce240f58d48effec.1307292171.git.luto@mit.edu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-05-26T19:19:31+00:00 Linus Torvalds torvalds@linux-foundation.org 2011-05-26T19:19:31+00:00 14587a2a25447813996e6fb9e48d48627cb75a5d * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: vdso: Remove unused variable x86-64: Optimize vDSO time() x86-64: Add time to vDSO x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSO x86-64: Move vread_tsc into a new file with sensible options x86-64: Vclock_gettime(CLOCK_MONOTONIC) can't ever see nsec < 0 x86-64: Don't generate cmov in vread_tsc x86-64: Remove unnecessary barrier in vread_tsc x86-64: Clean up vdso/kernel shared variables 
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: vdso: Remove unused variable
  x86-64: Optimize vDSO time()
  x86-64: Add time to vDSO
  x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSO
  x86-64: Move vread_tsc into a new file with sensible options
  x86-64: Vclock_gettime(CLOCK_MONOTONIC) can't ever see nsec < 0
  x86-64: Don't generate cmov in vread_tsc
  x86-64: Remove unnecessary barrier in vread_tsc
  x86-64: Clean up vdso/kernel shared variables