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| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2021-03-30 09:58:38 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-04-16 11:43:20 +0200 |
| commit | 1dcb3ebc24164c0b5d3b13696d80bf163e16b664 (patch) | |
| tree | 9ae055a7fb24c07674c56f9cc9852f4b554f388f /kernel/trace | |
| parent | 6c6d58322079f94d58e22eda1166240181ac3270 (diff) | |
| download | kernel_replicant_linux-1dcb3ebc24164c0b5d3b13696d80bf163e16b664.tar.gz kernel_replicant_linux-1dcb3ebc24164c0b5d3b13696d80bf163e16b664.tar.bz2 kernel_replicant_linux-1dcb3ebc24164c0b5d3b13696d80bf163e16b664.zip | |
ftrace: Check if pages were allocated before calling free_pages()
[ Upstream commit 59300b36f85f254260c81d9dd09195fa49eb0f98 ]
It is possible that on error pg->size can be zero when getting its order,
which would return a -1 value. It is dangerous to pass in an order of -1
to free_pages(). Check if order is greater than or equal to zero before
calling free_pages().
Link: https://lore.kernel.org/lkml/20210330093916.432697c7@gandalf.local.home/
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/ftrace.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 82041bbf8fc2..b1983c2aeb53 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3230,7 +3230,8 @@ ftrace_allocate_pages(unsigned long num_to_init) pg = start_pg; while (pg) { order = get_count_order(pg->size / ENTRIES_PER_PAGE); - free_pages((unsigned long)pg->records, order); + if (order >= 0) + free_pages((unsigned long)pg->records, order); start_pg = pg->next; kfree(pg); pg = start_pg; @@ -6452,7 +6453,8 @@ void ftrace_release_mod(struct module *mod) clear_mod_from_hashes(pg); order = get_count_order(pg->size / ENTRIES_PER_PAGE); - free_pages((unsigned long)pg->records, order); + if (order >= 0) + free_pages((unsigned long)pg->records, order); tmp_page = pg->next; kfree(pg); ftrace_number_of_pages -= 1 << order; @@ -6812,7 +6814,8 @@ void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) if (!pg->index) { *last_pg = pg->next; order = get_count_order(pg->size / ENTRIES_PER_PAGE); - free_pages((unsigned long)pg->records, order); + if (order >= 0) + free_pages((unsigned long)pg->records, order); ftrace_number_of_pages -= 1 << order; ftrace_number_of_groups--; kfree(pg); |