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Update syscall.c to use syscall_exit on failure instead of calling thread_exit directly

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This commit is contained in:
sBubshait
2024-11-13 18:02:08 +00:00
parent 4f586bb4da
commit 287130ca7b
1 changed files with 6 additions and 6 deletions
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12
src/userprog/syscall.c
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@@ -81,7 +81,6 @@ static const syscall_arguments syscall_lookup[] =
static const int LOOKUP_SIZE static const int LOOKUP_SIZE
= sizeof (syscall_lookup) / sizeof (syscall_arguments); = sizeof (syscall_lookup) / sizeof (syscall_arguments);
/* Initialises the syscall handling system, as well as a global lock to /* Initialises the syscall handling system, as well as a global lock to
synchronise all file access between processes. */ synchronise all file access between processes. */
void void
@@ -103,13 +102,14 @@ syscall_handler (struct intr_frame *f)
/* Ensures the number corresponds to a system call that can be handled. */ /* Ensures the number corresponds to a system call that can be handled. */
if (syscall_number >= LOOKUP_SIZE) if (syscall_number >= LOOKUP_SIZE)
thread_exit (); syscall_exit (EXIT_FAILURE);
syscall_arguments syscall = syscall_lookup[syscall_number]; syscall_arguments syscall = syscall_lookup[syscall_number];
/* Next, read and copy the arguments from the stack pointer. */ /* Next, read and copy the arguments from the stack pointer. */
validate_user_pointer (f->esp + sizeof (uintptr_t), validate_user_pointer (f->esp + sizeof (uintptr_t),
syscall.arity * sizeof (uintptr_t)); syscall.arity * sizeof (uintptr_t));
uintptr_t args[MAX_SYSCALL_ARGS] = {0}; uintptr_t args[MAX_SYSCALL_ARGS] = {0};
for (int i = 0; i < syscall.arity && i < MAX_SYSCALL_ARGS; i++) for (int i = 0; i < syscall.arity && i < MAX_SYSCALL_ARGS; i++)
args[i] = *(uintptr_t *) (f->esp + sizeof (uintptr_t) * (i + 1)); args[i] = *(uintptr_t *) (f->esp + sizeof (uintptr_t) * (i + 1));
@@ -427,13 +427,13 @@ validate_user_pointer (const void *start, size_t size)
const void *end = start + size - 1; const void *end = start + size - 1;
if (start == NULL || !is_user_vaddr (start) || !is_user_vaddr (end)) if (start == NULL || !is_user_vaddr (start) || !is_user_vaddr (end))
thread_exit (); syscall_exit (EXIT_FAILURE);
/* We now need to check if the entire memory block is mapped to physical /* We now need to check if the entire memory block is mapped to physical
memory by the page table. */ memory by the page table. */
for (const void *ptr = start; ptr <= end; ptr += PGSIZE) for (const void *ptr = start; ptr <= end; ptr += PGSIZE)
if (pagedir_get_page (thread_current ()->pagedir, ptr) == NULL) if (pagedir_get_page (thread_current ()->pagedir, ptr) == NULL)
thread_exit (); syscall_exit (EXIT_FAILURE);
} }
/* Validates if a string is fully contained within user virtual memory. Kills /* Validates if a string is fully contained within user virtual memory. Kills
@@ -443,7 +443,7 @@ static void
validate_user_string (const char *str) validate_user_string (const char *str)
{ {
if (str == NULL || !is_user_vaddr (str)) if (str == NULL || !is_user_vaddr (str))
thread_exit (); syscall_exit (EXIT_FAILURE);
size_t length = 0; size_t length = 0;
size_t offset = (uintptr_t) str % PGSIZE; size_t offset = (uintptr_t) str % PGSIZE;
@@ -455,7 +455,7 @@ validate_user_string (const char *str)
if (!is_user_vaddr(page) || if (!is_user_vaddr(page) ||
pagedir_get_page (thread_current ()->pagedir, page) == NULL) pagedir_get_page (thread_current ()->pagedir, page) == NULL)
thread_exit (); syscall_exit (EXIT_FAILURE);
while (offset < PGSIZE) while (offset < PGSIZE)
{ {