6.14-stable review patch. If anyone has any objections, please let me know.
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From: Anthony Iliopoulos ailiop@suse.com
[ Upstream commit 534f5a8ba27863141e29766467a3e1f61bcb47ac ]
get_stubs_size assumes that there must always be at least one patchable function entry, which is not always the case (modules that export data but no code), otherwise it returns -ENOEXEC and thus the section header sh_size is set to that value. During module_memory_alloc() the size is passed to execmem_alloc() after being page-aligned and thus set to zero which will cause it to fail the allocation (and thus module loading) as __vmalloc_node_range() checks for zero-sized allocs and returns null:
[ 115.466896] module_64: cast_common: doesn't contain __patchable_function_entries. [ 115.469189] ------------[ cut here ]------------ [ 115.469496] WARNING: CPU: 0 PID: 274 at mm/vmalloc.c:3778 __vmalloc_node_range_noprof+0x8b4/0x8f0 ... [ 115.478574] ---[ end trace 0000000000000000 ]--- [ 115.479545] execmem: unable to allocate memory
Fix this by removing the check completely, since it is anyway not helpful to propagate this as an error upwards.
Fixes: eec37961a56a ("powerpc64/ftrace: Move ftrace sequence out of line") Signed-off-by: Anthony Iliopoulos ailiop@suse.com Acked-by: Naveen N Rao (AMD) naveen@kernel.org Signed-off-by: Madhavan Srinivasan maddy@linux.ibm.com Link: https://patch.msgid.link/20250204231821.39140-1-ailiop@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/kernel/module_64.c | 4 ---- 1 file changed, 4 deletions(-)
diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c index 34a5aec4908fb..126bf3b06ab7e 100644 --- a/arch/powerpc/kernel/module_64.c +++ b/arch/powerpc/kernel/module_64.c @@ -258,10 +258,6 @@ static unsigned long get_stubs_size(const Elf64_Ehdr *hdr, break; } } - if (i == hdr->e_shnum) { - pr_err("%s: doesn't contain __patchable_function_entries.\n", me->name); - return -ENOEXEC; - } #endif
pr_debug("Looks like a total of %lu stubs, max\n", relocs);