svn commit: r337978 - in head/libexec/rtld-elf: . aarch64 arm mips powerpc powerpc64 riscv
Michal Meloun
melounmichal at gmail.com
Mon Aug 20 16:00:24 UTC 2018
On 17.08.2018 18:19, Brooks Davis wrote:
> Author: brooks
> Date: Fri Aug 17 16:19:47 2018
> New Revision: 337978
> URL: https://svnweb.freebsd.org/changeset/base/337978
>
> Log:
> Rework rtld's TLS Variant I implementation to match r326794
>
> The above commit fixed handling overaligned TLS segments in libc's
> TLS Variant I implementation, but rtld provides its own implementation
> for dynamically-linked executables which lacks these fixes. Thus,
> port these changes to rtld.
>
> Submitted by: James Clarke
> Reviewed by: kbowling
> Testing byL kbowling (powerpc64), br (riscv), kevans (armv7)
> Obtained from: CheriBSD
> Sponsored by: DARPA, AFRL
> Differential Revision: https://reviews.freebsd.org/D16510
>
> Modified:
> head/libexec/rtld-elf/aarch64/rtld_machdep.h
> head/libexec/rtld-elf/arm/rtld_machdep.h
> head/libexec/rtld-elf/mips/rtld_machdep.h
> head/libexec/rtld-elf/powerpc/rtld_machdep.h
> head/libexec/rtld-elf/powerpc64/rtld_machdep.h
> head/libexec/rtld-elf/riscv/rtld_machdep.h
> head/libexec/rtld-elf/rtld.c
>
This commit breaks TLS handling for (at least) armv7. Can you please
revert it until I will be able to identify where is problem?
In my case, the libc _ThreadRuneLocale symbol is not zero on program start.
Thanks,
Michal
> Modified: head/libexec/rtld-elf/aarch64/rtld_machdep.h
> ==============================================================================
> --- head/libexec/rtld-elf/aarch64/rtld_machdep.h Fri Aug 17 16:07:06 2018 (r337977)
> +++ head/libexec/rtld-elf/aarch64/rtld_machdep.h Fri Aug 17 16:19:47 2018 (r337978)
> @@ -69,6 +69,8 @@ Elf_Addr reloc_jmpslot(Elf_Addr *where, Elf_Addr targe
> #define calculate_tls_offset(prev_offset, prev_size, size, align) \
> round(prev_offset + prev_size, align)
> #define calculate_tls_end(off, size) ((off) + (size))
> +#define calculate_tls_post_size(align) \
> + round(TLS_TCB_SIZE, align) - TLS_TCB_SIZE
>
> #define TLS_TCB_SIZE 16
> typedef struct {
>
> Modified: head/libexec/rtld-elf/arm/rtld_machdep.h
> ==============================================================================
> --- head/libexec/rtld-elf/arm/rtld_machdep.h Fri Aug 17 16:07:06 2018 (r337977)
> +++ head/libexec/rtld-elf/arm/rtld_machdep.h Fri Aug 17 16:19:47 2018 (r337978)
> @@ -69,6 +69,8 @@ typedef struct {
> #define calculate_tls_offset(prev_offset, prev_size, size, align) \
> round(prev_offset + prev_size, align)
> #define calculate_tls_end(off, size) ((off) + (size))
> +#define calculate_tls_post_size(align) \
> + round(TLS_TCB_SIZE, align) - TLS_TCB_SIZE
>
> extern void *__tls_get_addr(tls_index *ti);
>
>
> Modified: head/libexec/rtld-elf/mips/rtld_machdep.h
> ==============================================================================
> --- head/libexec/rtld-elf/mips/rtld_machdep.h Fri Aug 17 16:07:06 2018 (r337977)
> +++ head/libexec/rtld-elf/mips/rtld_machdep.h Fri Aug 17 16:19:47 2018 (r337978)
> @@ -64,10 +64,11 @@ typedef struct {
> #define round(size, align) \
> (((size) + (align) - 1) & ~((align) - 1))
> #define calculate_first_tls_offset(size, align) \
> - round(TLS_TCB_SIZE, align)
> + TLS_TCB_SIZE
> #define calculate_tls_offset(prev_offset, prev_size, size, align) \
> round(prev_offset + prev_size, align)
> #define calculate_tls_end(off, size) ((off) + (size))
> +#define calculate_tls_post_size(align) 0
>
> extern void *__tls_get_addr(tls_index *ti);
>
>
> Modified: head/libexec/rtld-elf/powerpc/rtld_machdep.h
> ==============================================================================
> --- head/libexec/rtld-elf/powerpc/rtld_machdep.h Fri Aug 17 16:07:06 2018 (r337977)
> +++ head/libexec/rtld-elf/powerpc/rtld_machdep.h Fri Aug 17 16:19:47 2018 (r337978)
> @@ -74,10 +74,11 @@ void _rtld_powerpc_pltcall(void);
> #define round(size, align) \
> (((size) + (align) - 1) & ~((align) - 1))
> #define calculate_first_tls_offset(size, align) \
> - round(8, align)
> + TLS_TCB_SIZE
> #define calculate_tls_offset(prev_offset, prev_size, size, align) \
> round(prev_offset + prev_size, align)
> #define calculate_tls_end(off, size) ((off) + (size))
> +#define calculate_tls_post_size(align) 0
>
> typedef struct {
> unsigned long ti_module;
>
> Modified: head/libexec/rtld-elf/powerpc64/rtld_machdep.h
> ==============================================================================
> --- head/libexec/rtld-elf/powerpc64/rtld_machdep.h Fri Aug 17 16:07:06 2018 (r337977)
> +++ head/libexec/rtld-elf/powerpc64/rtld_machdep.h Fri Aug 17 16:19:47 2018 (r337978)
> @@ -66,10 +66,11 @@ Elf_Addr reloc_jmpslot(Elf_Addr *where, Elf_Addr targe
> #define round(size, align) \
> (((size) + (align) - 1) & ~((align) - 1))
> #define calculate_first_tls_offset(size, align) \
> - round(16, align)
> + TLS_TCB_SIZE
> #define calculate_tls_offset(prev_offset, prev_size, size, align) \
> round(prev_offset + prev_size, align)
> #define calculate_tls_end(off, size) ((off) + (size))
> +#define calculate_tls_post_size(align) 0
>
> typedef struct {
> unsigned long ti_module;
>
> Modified: head/libexec/rtld-elf/riscv/rtld_machdep.h
> ==============================================================================
> --- head/libexec/rtld-elf/riscv/rtld_machdep.h Fri Aug 17 16:07:06 2018 (r337977)
> +++ head/libexec/rtld-elf/riscv/rtld_machdep.h Fri Aug 17 16:19:47 2018 (r337978)
> @@ -89,10 +89,11 @@ Elf_Addr reloc_jmpslot(Elf_Addr *where, Elf_Addr targe
> #define round(size, align) \
> (((size) + (align) - 1) & ~((align) - 1))
> #define calculate_first_tls_offset(size, align) \
> - round(16, align)
> + TLS_TCB_SIZE
> #define calculate_tls_offset(prev_offset, prev_size, size, align) \
> round(prev_offset + prev_size, align)
> #define calculate_tls_end(off, size) ((off) + (size))
> +#define calculate_tls_post_size(align) 0
>
> typedef struct {
> unsigned long ti_module;
>
> Modified: head/libexec/rtld-elf/rtld.c
> ==============================================================================
> --- head/libexec/rtld-elf/rtld.c Fri Aug 17 16:07:06 2018 (r337977)
> +++ head/libexec/rtld-elf/rtld.c Fri Aug 17 16:19:47 2018 (r337978)
> @@ -4693,47 +4693,87 @@ tls_get_addr_common(Elf_Addr **dtvp, int index, size_t
> defined(__powerpc__) || defined(__riscv)
>
> /*
> + * Return pointer to allocated TLS block
> + */
> +static void *
> +get_tls_block_ptr(void *tcb, size_t tcbsize)
> +{
> + size_t extra_size, post_size, pre_size, tls_block_size;
> + size_t tls_init_align;
> +
> + tls_init_align = MAX(obj_main->tlsalign, 1);
> +
> + /* Compute fragments sizes. */
> + extra_size = tcbsize - TLS_TCB_SIZE;
> + post_size = calculate_tls_post_size(tls_init_align);
> + tls_block_size = tcbsize + post_size;
> + pre_size = roundup2(tls_block_size, tls_init_align) - tls_block_size;
> +
> + return ((char *)tcb - pre_size - extra_size);
> +}
> +
> +/*
> * Allocate Static TLS using the Variant I method.
> + *
> + * For details on the layout, see lib/libc/gen/tls.c.
> + *
> + * NB: rtld's tls_static_space variable includes TLS_TCB_SIZE and post_size as
> + * it is based on tls_last_offset, and TLS offsets here are really TCB
> + * offsets, whereas libc's tls_static_space is just the executable's static
> + * TLS segment.
> */
> void *
> allocate_tls(Obj_Entry *objs, void *oldtcb, size_t tcbsize, size_t tcbalign)
> {
> Obj_Entry *obj;
> - char *tcb;
> - Elf_Addr **tls;
> - Elf_Addr *dtv;
> + char *tls_block;
> + Elf_Addr *dtv, **tcb;
> Elf_Addr addr;
> int i;
> + size_t extra_size, maxalign, post_size, pre_size, tls_block_size;
> + size_t tls_init_align;
>
> if (oldtcb != NULL && tcbsize == TLS_TCB_SIZE)
> return (oldtcb);
>
> assert(tcbsize >= TLS_TCB_SIZE);
> - tcb = xcalloc(1, tls_static_space - TLS_TCB_SIZE + tcbsize);
> - tls = (Elf_Addr **)(tcb + tcbsize - TLS_TCB_SIZE);
> + maxalign = MAX(tcbalign, tls_static_max_align);
> + tls_init_align = MAX(obj_main->tlsalign, 1);
>
> + /* Compute fragmets sizes. */
> + extra_size = tcbsize - TLS_TCB_SIZE;
> + post_size = calculate_tls_post_size(tls_init_align);
> + tls_block_size = tcbsize + post_size;
> + pre_size = roundup2(tls_block_size, tls_init_align) - tls_block_size;
> + tls_block_size += pre_size + tls_static_space - TLS_TCB_SIZE - post_size;
> +
> + /* Allocate whole TLS block */
> + tls_block = malloc_aligned(tls_block_size, maxalign);
> + tcb = (Elf_Addr **)(tls_block + pre_size + extra_size);
> +
> if (oldtcb != NULL) {
> - memcpy(tls, oldtcb, tls_static_space);
> - free(oldtcb);
> + memcpy(tls_block, get_tls_block_ptr(oldtcb, tcbsize),
> + tls_static_space);
> + free_aligned(get_tls_block_ptr(oldtcb, tcbsize));
>
> /* Adjust the DTV. */
> - dtv = tls[0];
> + dtv = tcb[0];
> for (i = 0; i < dtv[1]; i++) {
> if (dtv[i+2] >= (Elf_Addr)oldtcb &&
> dtv[i+2] < (Elf_Addr)oldtcb + tls_static_space) {
> - dtv[i+2] = dtv[i+2] - (Elf_Addr)oldtcb + (Elf_Addr)tls;
> + dtv[i+2] = dtv[i+2] - (Elf_Addr)oldtcb + (Elf_Addr)tcb;
> }
> }
> } else {
> dtv = xcalloc(tls_max_index + 2, sizeof(Elf_Addr));
> - tls[0] = dtv;
> + tcb[0] = dtv;
> dtv[0] = tls_dtv_generation;
> dtv[1] = tls_max_index;
>
> for (obj = globallist_curr(objs); obj != NULL;
> obj = globallist_next(obj)) {
> if (obj->tlsoffset > 0) {
> - addr = (Elf_Addr)tls + obj->tlsoffset;
> + addr = (Elf_Addr)tcb + obj->tlsoffset;
> if (obj->tlsinitsize > 0)
> memcpy((void*) addr, obj->tlsinit, obj->tlsinitsize);
> if (obj->tlssize > obj->tlsinitsize)
> @@ -4752,14 +4792,19 @@ free_tls(void *tcb, size_t tcbsize, size_t tcbalign)
> {
> Elf_Addr *dtv;
> Elf_Addr tlsstart, tlsend;
> - int dtvsize, i;
> + size_t post_size;
> + size_t dtvsize, i, tls_init_align;
>
> assert(tcbsize >= TLS_TCB_SIZE);
> + tls_init_align = MAX(obj_main->tlsalign, 1);
>
> - tlsstart = (Elf_Addr)tcb + tcbsize - TLS_TCB_SIZE;
> - tlsend = tlsstart + tls_static_space;
> + /* Compute fragments sizes. */
> + post_size = calculate_tls_post_size(tls_init_align);
>
> - dtv = *(Elf_Addr **)tlsstart;
> + tlsstart = (Elf_Addr)tcb + TLS_TCB_SIZE + post_size;
> + tlsend = (Elf_Addr)tcb + tls_static_space;
> +
> + dtv = *(Elf_Addr **)tcb;
> dtvsize = dtv[1];
> for (i = 0; i < dtvsize; i++) {
> if (dtv[i+2] && (dtv[i+2] < tlsstart || dtv[i+2] >= tlsend)) {
> @@ -4767,7 +4812,7 @@ free_tls(void *tcb, size_t tcbsize, size_t tcbalign)
> }
> }
> free(dtv);
> - free(tcb);
> + free_aligned(get_tls_block_ptr(tcb, tcbsize));
> }
>
> #endif
>
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