diff options
Diffstat (limited to 'kernel/exec.c')
| -rw-r--r-- | kernel/exec.c | 21 |
1 files changed, 16 insertions, 5 deletions
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); |