swh:1:snp:77163734605b0ec556b01d897b7bb4a7e30d46b6
Revision b71dbf1032f546bf3efd60fb5d9d0cefd200a508 authored by Darrick J. Wong on 15 September 2016, 03:20:44 UTC, committed by Linus Torvalds on 15 September 2016, 20:29:52 UTC
Kirill A Shutemov reports that the kernel doesn't try to cap dest_count in any way, and uses the number to allocate kernel memory. This causes high order allocation warnings in the kernel log if someone passes in a big enough value. We should clamp the allocation at PAGE_SIZE to avoid stressing the VM. The two existing users of the dedupe ioctl never send more than 120 requests, so we can safely clamp dest_range at PAGE_SIZE, because with 4k pages we can handle up to 127 dedupe candidates. Given the max extent length of 16MB, we can end up doing 2GB of IO which is plenty. [ Note: the "offsetof()" can't overflow, because 'count' is just a 16-bit integer. That's not obvious in the limited context of the patch, so I'm noting it here because it made me go look. - Linus ] Reported-by: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 5297e0f
Tip revision: a4412fdd49dc011bcc2c0d81ac4cab7457092650 authored by Steven Rostedt (Google) on 21 November 2022, 15:44:03 UTC
error-injection: Add prompt for function error injection
error-injection: Add prompt for function error injection
Tip revision: a4412fd
File | Mode | Size |
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Documentation | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.cocciconfig | -rw-r--r-- | 59 bytes |
.get_maintainer.ignore | -rw-r--r-- | 31 bytes |
.gitignore | -rw-r--r-- | 1.3 KB |
.mailmap | -rw-r--r-- | 7.3 KB |
COPYING | -rw-r--r-- | 18.3 KB |
CREDITS | -rw-r--r-- | 95.5 KB |
Kbuild | -rw-r--r-- | 2.8 KB |
Kconfig | -rw-r--r-- | 252 bytes |
MAINTAINERS | -rw-r--r-- | 363.6 KB |
Makefile | -rw-r--r-- | 56.8 KB |
README | -rw-r--r-- | 18.1 KB |
REPORTING-BUGS | -rw-r--r-- | 7.3 KB |
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