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| author | 2018-08-06 12:45:42 +0200 | |
|---|---|---|
| committer | 2018-08-06 12:45:42 +0200 | |
| commit | 9e90c7985229430428dc9ba0ec7fe422901b456d (patch) | |
| tree | cae2072feba8cc433a32d96568bbcf36070bd6e5 /fs/proc/base.c | |
| parent | genirq/irqchip: Remove MULTI_IRQ_HANDLER as it's now obselete (diff) | |
| parent | irqchip/gic-v3-its: Make its_lock a raw_spin_lock_t (diff) | |
| download | wireguard-linux-9e90c7985229430428dc9ba0ec7fe422901b456d.tar.xz wireguard-linux-9e90c7985229430428dc9ba0ec7fe422901b456d.zip | |
Merge tag 'irqchip-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates from Marc Zyngier:
- GICv3 ITS LPI allocation revamp
- GICv3 support for hypervisor-enforced LPI range
- GICv3 ITS conversion to raw spinlock
Diffstat (limited to 'fs/proc/base.c')
| -rw-r--r-- | fs/proc/base.c | 28 |
1 files changed, 23 insertions, 5 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index b6572944efc3..aaffc0c30216 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -235,6 +235,10 @@ static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, if (env_start != arg_end || env_start >= env_end) env_start = env_end = arg_end; + /* .. and limit it to a maximum of one page of slop */ + if (env_end >= arg_end + PAGE_SIZE) + env_end = arg_end + PAGE_SIZE - 1; + /* We're not going to care if "*ppos" has high bits set */ pos = arg_start + *ppos; @@ -254,10 +258,19 @@ static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, while (count) { int got; size_t size = min_t(size_t, PAGE_SIZE, count); + long offset; - got = access_remote_vm(mm, pos, page, size, FOLL_ANON); - if (got <= 0) + /* + * Are we already starting past the official end? + * We always include the last byte that is *supposed* + * to be NUL + */ + offset = (pos >= arg_end) ? pos - arg_end + 1 : 0; + + got = access_remote_vm(mm, pos - offset, page, size + offset, FOLL_ANON); + if (got <= offset) break; + got -= offset; /* Don't walk past a NUL character once you hit arg_end */ if (pos + got >= arg_end) { @@ -276,12 +289,17 @@ static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, n = arg_end - pos - 1; /* Cut off at first NUL after 'n' */ - got = n + strnlen(page+n, got-n); - if (!got) + got = n + strnlen(page+n, offset+got-n); + if (got < offset) break; + got -= offset; + + /* Include the NUL if it existed */ + if (got < size) + got++; } - got -= copy_to_user(buf, page, got); + got -= copy_to_user(buf, page+offset, got); if (unlikely(!got)) { if (!len) len = -EFAULT; |
