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* Update copyright dates with scripts/update-copyrights.Joseph Myers2018-01-011-1/+1
| | | | | | | * All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
* x86: Make a space in jmpbuf for shadow stack pointerH.J. Lu2017-11-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To support Shadow Stack (SHSTK) in Intel Control-flow Enforcement Technology (CET) in setjmp/longjmp, we need to save shadow stack pointer in jmp_buf. The __saved_mask field in jmp_buf has type of __sigset_t. On Linux, __sigset_t is defined as #define _SIGSET_NWORDS (1024 / (8 * sizeof (unsigned long int))) typedef struct { unsigned long int __val[_SIGSET_NWORDS]; } __sigset_t; which is much bigger than expected by the __sigprocmask system call, which has typedef struct { unsigned long sig[_NSIG_WORDS]; } sigset_t; For Linux/x86, we can shrink __sigset_t used by __saved_mask in jmp_buf to add paddings for shadow stack pointer. As long as the new __sigset_t is not smaller than sigset_t expected by the __sigprocmask system call, it should work correctly. This patch adds an internal header file, <setjmpP.h>, to define __jmp_buf_sigset_t for __saved_mask in jmp_buf for Linux/x86 with a space to store shadow stack pointer. It verifies __jmp_buf_sigset_t has the suitable size for the __sigprocmask system call. A run-time test, tst-saved_mask-1.c, is added to verify that size of __jmp_buf_sigset_t is sufficient. If its size is too small, the test fails with rt_sigprocmask(SIG_SETMASK, strace: umoven: short read (4 < 8) @0x7fa8aa28effc 0x7fa8aa28effc, NULL, 8) = -1 EFAULT (Bad address) rt_sigprocmask(SIG_SETMASK, strace: umoven: short read (4 < 8) @0x7fa8aa28effc 0x7fa8aa28effc, NULL, 8) = -1 EFAULT (Bad address) rt_sigprocmask(SIG_SETMASK, NULL, 0x7fa8aa28effc, 8) = -1 EFAULT (Bad address) exit_group(1) = ? Tested with build-many-glibcs.py. * debug/longjmp_chk.c: Include <setjmpP.h> instead of <setjmp.h>. * setjmp/longjmp.c: Include <setjmpP.h> instead of <setjmp.h>. (__libc_siglongjmp): Cast &env[0].__saved_mask to "sigset_t *". * setjmp/sigjmp.c: Include <setjmpP.h> instead of <setjmp.h>. (__sigjmp_save): Cast &env[0].__saved_mask to "sigset_t *". * sysdeps/generic/setjmpP.h: New file. * sysdeps/unix/sysv/linux/x86/jmp_buf-ssp.sym: Likewise. * sysdeps/unix/sysv/linux/x86/setjmpP.h: Likewise. * sysdeps/unix/sysv/linux/x86/tst-saved_mask-1.c: Likewise. * sysdeps/unix/sysv/linux/x86/Makefile (gen-as-const-headers): Add jmp_buf-ssp.sym. (tests): Add tst-saved_mask-1.
* Move ____longjmp_chk prototype to include/setjmp.hH.J. Lu2017-08-201-4/+0
| | | | | | | | | Move ____longjmp_chk prototype to include/setjmp.h and add attribute_hidden. * debug/longjmp_chk.c (____longjmp_chk): Moved to ... * include/setjmp.h (____longjmp_chk): Here. Add attribute_hidden.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-011-1/+1
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* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-041-1/+1
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* Update copyright dates with scripts/update-copyrights.Joseph Myers2015-01-021-1/+1
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* Update copyright notices with scripts/update-copyrightsAllan McRae2014-01-011-1/+1
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* Update copyright notices with scripts/update-copyrights.Joseph Myers2013-01-021-1/+1
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* Replace FSF snail mail address with URLs.Paul Eggert2012-02-091-3/+2
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* Check for valid stack frame in longjmp.Ulrich Drepper2009-05-151-0/+28
If longjmp restores the stack frame to an address which is beyond the stack frame at the time of the longjmp call it would install an uninitialized stack frame. If compiled with _FORTIFY_SOURCE defined, longjmp will now bail out in this situation.