diff options
author | Michal Hocko <mhocko@suse.com> | 2016-05-23 16:25:36 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-05-23 17:04:14 -0700 |
commit | 864778b154233d3a673c520aa9606777589ecee7 (patch) | |
tree | 422b045224098ec95b23b1da8a441e25ee52288e /arch/x86/ia32/ia32_aout.c | |
parent | ae7987835643e470cb220e6685bd36d92179ef9c (diff) | |
download | op-kernel-dev-864778b154233d3a673c520aa9606777589ecee7.zip op-kernel-dev-864778b154233d3a673c520aa9606777589ecee7.tar.gz |
mm, aout: handle vm_brk failures
vm_brk is allowed to fail but load_aout_binary simply ignores the error
and happily continues. I haven't noticed any problem from that in real
life but later patches will make the failure more likely because vm_brk
will become killable (resp. mmap_sem for write waiting will become
killable) so we should be more careful now.
The error handling should be quite straightforward because there are
calls to vm_mmap which check the error properly already. The only
notable exception is set_brk which is called after beyond_if label. But
nothing indicates that we cannot move it above set_binfmt as the two do
not depend on each other and fail before we do set_binfmt and alter
reference counting.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86/ia32/ia32_aout.c')
-rw-r--r-- | arch/x86/ia32/ia32_aout.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c index ae6aad1..f5e737f 100644 --- a/arch/x86/ia32/ia32_aout.c +++ b/arch/x86/ia32/ia32_aout.c @@ -116,13 +116,13 @@ static struct linux_binfmt aout_format = { .min_coredump = PAGE_SIZE }; -static void set_brk(unsigned long start, unsigned long end) +static unsigned long set_brk(unsigned long start, unsigned long end) { start = PAGE_ALIGN(start); end = PAGE_ALIGN(end); if (end <= start) - return; - vm_brk(start, end - start); + return start; + return vm_brk(start, end - start); } #ifdef CONFIG_COREDUMP @@ -349,7 +349,10 @@ static int load_aout_binary(struct linux_binprm *bprm) #endif if (!bprm->file->f_op->mmap || (fd_offset & ~PAGE_MASK) != 0) { - vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data); + error = vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data); + if (IS_ERR_VALUE(error)) + return error; + read_code(bprm->file, N_TXTADDR(ex), fd_offset, ex.a_text+ex.a_data); goto beyond_if; @@ -372,10 +375,13 @@ static int load_aout_binary(struct linux_binprm *bprm) if (error != N_DATADDR(ex)) return error; } + beyond_if: - set_binfmt(&aout_format); + error = set_brk(current->mm->start_brk, current->mm->brk); + if (IS_ERR_VALUE(error)) + return error; - set_brk(current->mm->start_brk, current->mm->brk); + set_binfmt(&aout_format); current->mm->start_stack = (unsigned long)create_aout_tables((char __user *)bprm->p, bprm); @@ -434,7 +440,9 @@ static int load_aout_library(struct file *file) error_time = jiffies; } #endif - vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss); + retval = vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss); + if (IS_ERR_VALUE(retval)) + goto out; read_code(file, start_addr, N_TXTOFF(ex), ex.a_text + ex.a_data); |