@@ -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);
/*
@@ -763,7 +767,7 @@ initialize_relocation_hashtable(unsigned int num_relocations,
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);
When there is not enough allocatable memory for the relocation hashtable, module loading should exit gracefully. Previously, this was attempted to be accomplished by checking if an unsigned number is less than zero which does not work. Instead have the caller check if the hashtable was correctly allocated and add a comment explaining that hashtable_bits that is 0 is valid. Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> Fixes: d8792a5734b0 ("riscv: Safely remove entries from relocation list") Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/r/202312132019.iYGTwW0L-lkp@intel.com/ Reported-by: kernel test robot <lkp@intel.com> Reported-by: Julia Lawall <julia.lawall@inria.fr> Closes: https://lore.kernel.org/r/202312120044.wTI1Uyaa-lkp@intel.com/ --- arch/riscv/kernel/module.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)