diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/defs.h | 2 | ||||
| -rw-r--r-- | kernel/exec.c | 21 | ||||
| -rw-r--r-- | kernel/proc.c | 2 | ||||
| -rw-r--r-- | kernel/vm.c | 4 |
4 files changed, 20 insertions, 9 deletions
diff --git a/kernel/defs.h b/kernel/defs.h index 7457b66..95fb94b 100644 --- a/kernel/defs.h +++ b/kernel/defs.h @@ -162,7 +162,7 @@ void kvmmap(pagetable_t, uint64, uint64, uint64, int); int mappages(pagetable_t, uint64, uint64, uint64, int); pagetable_t uvmcreate(void); void uvmfirst(pagetable_t, uchar *, uint); -uint64 uvmalloc(pagetable_t, uint64, uint64); +uint64 uvmalloc(pagetable_t, uint64, uint64, int); uint64 uvmdealloc(pagetable_t, uint64, uint64); int uvmcopy(pagetable_t, pagetable_t, uint64); void uvmfree(pagetable_t, uint64); diff --git a/kernel/exec.c b/kernel/exec.c index 09b4bdc..e18bbb6 100644 --- a/kernel/exec.c +++ b/kernel/exec.c @@ -7,7 +7,17 @@ #include "defs.h" #include "elf.h" -static int loadseg(pde_t *pgdir, uint64 addr, struct inode *ip, uint offset, uint sz); +static int loadseg(pde_t *, uint64, struct inode *, uint, uint); + +int flags2perm(int flags) +{ + int perm = 0; + if(flags & 0x1) + perm = PTE_X; + if(flags & 0x2) + perm |= PTE_W; + return perm; +} int exec(char *path, char **argv) @@ -32,6 +42,7 @@ exec(char *path, char **argv) // Check ELF header if(readi(ip, 0, (uint64)&elf, 0, sizeof(elf)) != sizeof(elf)) goto bad; + if(elf.magic != ELF_MAGIC) goto bad; @@ -48,12 +59,12 @@ exec(char *path, char **argv) goto bad; if(ph.vaddr + ph.memsz < ph.vaddr) goto bad; + if(ph.vaddr % PGSIZE != 0) + goto bad; uint64 sz1; - if((sz1 = uvmalloc(pagetable, sz, ph.vaddr + ph.memsz)) == 0) + if((sz1 = uvmalloc(pagetable, sz, ph.vaddr + ph.memsz, flags2perm(ph.flags))) == 0) goto bad; sz = sz1; - if((ph.vaddr % PGSIZE) != 0) - goto bad; if(loadseg(pagetable, ph.vaddr, ip, ph.off, ph.filesz) < 0) goto bad; } @@ -69,7 +80,7 @@ exec(char *path, char **argv) // Use the second as the user stack. sz = PGROUNDUP(sz); uint64 sz1; - if((sz1 = uvmalloc(pagetable, sz, sz + 2*PGSIZE)) == 0) + if((sz1 = uvmalloc(pagetable, sz, sz + 2*PGSIZE, PTE_W)) == 0) goto bad; sz = sz1; uvmclear(pagetable, sz-2*PGSIZE); diff --git a/kernel/proc.c b/kernel/proc.c index 8d0ca8c..959b778 100644 --- a/kernel/proc.c +++ b/kernel/proc.c @@ -264,7 +264,7 @@ growproc(int n) sz = p->sz; if(n > 0){ - if((sz = uvmalloc(p->pagetable, sz, sz + n)) == 0) { + if((sz = uvmalloc(p->pagetable, sz, sz + n, PTE_W)) == 0) { return -1; } } else if(n < 0){ diff --git a/kernel/vm.c b/kernel/vm.c index 3c6f295..284b72d 100644 --- a/kernel/vm.c +++ b/kernel/vm.c @@ -218,7 +218,7 @@ uvmfirst(pagetable_t pagetable, uchar *src, uint sz) // Allocate PTEs and physical memory to grow process from oldsz to // newsz, which need not be page aligned. Returns new size or 0 on error. uint64 -uvmalloc(pagetable_t pagetable, uint64 oldsz, uint64 newsz) +uvmalloc(pagetable_t pagetable, uint64 oldsz, uint64 newsz, int xperm) { char *mem; uint64 a; @@ -234,7 +234,7 @@ uvmalloc(pagetable_t pagetable, uint64 oldsz, uint64 newsz) return 0; } memset(mem, 0, PGSIZE); - if(mappages(pagetable, a, PGSIZE, (uint64)mem, PTE_W|PTE_X|PTE_R|PTE_U) != 0){ + if(mappages(pagetable, a, PGSIZE, (uint64)mem, PTE_R|PTE_U|xperm) != 0){ kfree(mem); uvmdealloc(pagetable, a, oldsz); return 0; |