Unverified Commit 3a582750 authored by Palmer Dabbelt's avatar Palmer Dabbelt
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Merge patch series "riscv: modules: Fix module loading error handling" 

Charlie Jenkins <charlie@rivosinc.com> says:

When modules are loaded while there is not ample allocatable memory,
there was previously not proper error handling. This series fixes a
use-after-free error and a different issue that caused a non graceful
exit after memory was not properly allocated.

* b4-shazam-merge:
  riscv: Fix relocation_hashtable size
  riscv: Correctly free relocation hashtable on error
  riscv: Fix module loading free order

Link: https://lore.kernel.org/r/20240104-module_loading_fix-v3-0-a71f8de6ce0f@rivosinc.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parents 17f2c308 a35551c7

arch/riscv/kernel/module.c

+9 −5
Original line number Diff line number Diff line
@@ -723,8 +723,8 @@ static int add_relocation_to_accumulate(struct module *me, int type, 


			if (!bucket) {

				kfree(entry);

				kfree(rel_head);

				kfree(rel_head->rel_entry);

				kfree(rel_head);

				return -ENOMEM;

			}
@@ -747,6 +747,10 @@ initialize_relocation_hashtable(unsigned int num_relocations, 
{

	/* Can safely assume that bits is not greater than sizeof(long) */

	unsigned long hashtable_size = roundup_pow_of_two(num_relocations);

	/*

	 * When hashtable_size == 1, hashtable_bits == 0.

	 * This is valid because the hashing algorithm returns 0 in this case.

	 */

	unsigned int hashtable_bits = ilog2(hashtable_size);



	/*
@@ -760,10 +764,10 @@ initialize_relocation_hashtable(unsigned int num_relocations, 
	hashtable_size <<= should_double_size;



	*relocation_hashtable = kmalloc_array(hashtable_size,

					      sizeof(*relocation_hashtable),

					      sizeof(**relocation_hashtable),

					      GFP_KERNEL);

	if (!*relocation_hashtable)

		return -ENOMEM;

		return 0;



	__hash_init(*relocation_hashtable, hashtable_size);
@@ -789,8 +793,8 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, 
	hashtable_bits = initialize_relocation_hashtable(num_relocations,

							 &relocation_hashtable);



	if (hashtable_bits < 0)

		return hashtable_bits;

	if (!relocation_hashtable)

		return -ENOMEM;



	INIT_LIST_HEAD(&used_buckets_list);