6.5-stable review patch. If anyone has any objections, please let me know.
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From: James Morse james.morse@arm.com
commit f928f8b1a2496e7af95b860f9acf553f20f68f16 upstream.
Today module_frob_arch_sections() spots init sections from their 'init' prefix, and uses this to keep the init PLTs separate from the rest.
module_emit_plt_entry() uses within_module_init() to determine if a location is in the init text or not, but this depends on whether core code thought this was an init section.
Naturally the logic is different.
module_init_layout_section() groups the init and exit text together if module unloading is disabled, as the exit code will never run. The result is kernels with this configuration can't load all their modules because there are not enough PLTs for the combined init+exit section.
This results in the following: | WARNING: CPU: 2 PID: 51 at arch/arm64/kernel/module-plts.c:99 module_emit_plt_entry+0x184/0x1cc | Modules linked in: crct10dif_common | CPU: 2 PID: 51 Comm: modprobe Not tainted 6.5.0-rc4-yocto-standard-dirty #15208 | Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 | pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : module_emit_plt_entry+0x184/0x1cc | lr : module_emit_plt_entry+0x94/0x1cc | sp : ffffffc0803bba60 [...] | Call trace: | module_emit_plt_entry+0x184/0x1cc | apply_relocate_add+0x2bc/0x8e4 | load_module+0xe34/0x1bd4 | init_module_from_file+0x84/0xc0 | __arm64_sys_finit_module+0x1b8/0x27c | invoke_syscall.constprop.0+0x5c/0x104 | do_el0_svc+0x58/0x160 | el0_svc+0x38/0x110 | el0t_64_sync_handler+0xc0/0xc4 | el0t_64_sync+0x190/0x194
A previous patch exposed module_init_layout_section(), use that so the logic is the same.
Reported-by: Adam Johnston adam.johnston@arm.com Tested-by: Adam Johnston adam.johnston@arm.com Fixes: 055f23b74b20 ("module: check for exit sections in layout_sections() instead of module_init_section()") Cc: stable@vger.kernel.org # 5.15.x: 60a0aab7463ee69 arm64: module-plts: inline linux/moduleloader.h Cc: stable@vger.kernel.org # 5.15.x Signed-off-by: James Morse james.morse@arm.com Acked-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Luis Chamberlain mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/kernel/module-plts.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm64/kernel/module-plts.c +++ b/arch/arm64/kernel/module-plts.c @@ -339,7 +339,7 @@ int module_frob_arch_sections(Elf_Ehdr * if (nents) sort(rels, nents, sizeof(Elf64_Rela), cmp_rela, NULL);
- if (!str_has_prefix(secstrings + dstsec->sh_name, ".init")) + if (!module_init_layout_section(secstrings + dstsec->sh_name)) core_plts += count_plts(syms, rels, numrels, sechdrs[i].sh_info, dstsec); else