R. Christian McDonald d39e0bdc6b rtld/arm: fix initial-exec (IE) thread-local storage relocation ... net/frr[89] revealed an interesting edge-case on arm when dynamically linking a shared library that declares more than one static TLS variable with at least one using the "initial-exec" TLS model. In the case of frr[89], this library was libfrr.so which essentially does the following: #include <stdio.h> #include "lib.h" static __thread int *a __attribute__((tls_model("initial-exec"))); void lib_test() { static __thread int b = -1; printf("&a = %p\n", &a); printf(" a = %p\n", a); printf("\n"); printf("&b = %p\n", &b); printf(" b = %d\n", b); } Allocates a file scoped `static __thread` pointer with tls_model("initial-exec") and later a block scoped TLS int. Notice in the above minimal reproducer, `b == -1`. The relocation process does the wrong thing and ends up pointing both `a` and `b` at the same place in memory. The output of the above in the broken state is: &a = 0x4009c018 a = 0xffffffff &b = 0x4009c018 b = -1 With the patch applied, the output becomes: &a = 0x4009c01c a = 0x0 &b = 0x4009c018 b = -1 Reviewed by: kib Approved by: kp (mentor) Sponsored by: Rubicon Communications, LLC ("Netgate") Differential Revision: https://reviews.freebsd.org/D42415/ (cherry picked from commit 98fd69f0090da73d9d0451bd769d7752468284c6)		2024-11-22 10:35:06 -05:00
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Makefile.inc	Remove $FreeBSD$: one-line sh pattern	2023-08-16 11:55:03 -06:00
reloc.c	rtld/arm: fix initial-exec (IE) thread-local storage relocation	2024-11-22 10:35:06 -05:00
rtld_machdep.h	rtld: Add MD_OBJ_ENTRY to extend Struct_Obj_Entry	2024-07-15 12:24:58 +00:00
rtld_start.S	Remove $FreeBSD$: one-line .c pattern	2023-08-16 11:54:42 -06:00