From: Len Baker Date: Sat, 4 Sep 2021 15:41:06 +0000 (+0200) Subject: drm/radeon: Prefer kcalloc over open coded arithmetic X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=67684fcbdd0ef60a52f15e74e0e8a85edc867ce4;p=uclinux-h8%2Flinux.git drm/radeon: Prefer kcalloc over open coded arithmetic As noted in the "Deprecated Interfaces, Language Features, Attributes, and Conventions" documentation [1], size calculations (especially multiplication) should not be performed in memory allocator (or similar) function arguments due to the risk of them overflowing. This could lead to values wrapping around and a smaller allocation being made than the caller was expecting. Using those allocations could lead to linear overflows of heap memory and other misbehaviors. So, refactor the code a bit to use the purpose specific kcalloc() function instead of the calculated size argument in the kzalloc() function. [1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments Signed-off-by: Len Baker Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/radeon/r600_dpm.c b/drivers/gpu/drm/radeon/r600_dpm.c index 35b77c944701..fd4226b99862 100644 --- a/drivers/gpu/drm/radeon/r600_dpm.c +++ b/drivers/gpu/drm/radeon/r600_dpm.c @@ -820,12 +820,12 @@ union fan_info { static int r600_parse_clk_voltage_dep_table(struct radeon_clock_voltage_dependency_table *radeon_table, ATOM_PPLIB_Clock_Voltage_Dependency_Table *atom_table) { - u32 size = atom_table->ucNumEntries * - sizeof(struct radeon_clock_voltage_dependency_entry); int i; ATOM_PPLIB_Clock_Voltage_Dependency_Record *entry; - radeon_table->entries = kzalloc(size, GFP_KERNEL); + radeon_table->entries = kcalloc(atom_table->ucNumEntries, + sizeof(struct radeon_clock_voltage_dependency_entry), + GFP_KERNEL); if (!radeon_table->entries) return -ENOMEM;