diff options
Diffstat (limited to 'fs/file.c')
| -rw-r--r-- | fs/file.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/fs/file.c b/fs/file.c index b6fb6d18ac3b..4579c3296498 100644 --- a/fs/file.c +++ b/fs/file.c @@ -126,6 +126,21 @@ static struct fdtable * alloc_fdtable(unsigned int nr) if (unlikely(nr > sysctl_nr_open)) nr = ((sysctl_nr_open - 1) | (BITS_PER_LONG - 1)) + 1; + /* + * Check if the allocation size would exceed INT_MAX. kvmalloc_array() + * and kvmalloc() will warn if the allocation size is greater than + * INT_MAX, as filp_cachep objects are not __GFP_NOWARN. + * + * This can happen when sysctl_nr_open is set to a very high value and + * a process tries to use a file descriptor near that limit. For example, + * if sysctl_nr_open is set to 1073741816 (0x3ffffff8) - which is what + * systemd typically sets it to - then trying to use a file descriptor + * close to that value will require allocating a file descriptor table + * that exceeds 8GB in size. + */ + if (unlikely(nr > INT_MAX / sizeof(struct file *))) + return ERR_PTR(-EMFILE); + fdt = kmalloc(sizeof(struct fdtable), GFP_KERNEL_ACCOUNT); if (!fdt) goto out; |