From: Senthil Balasubramanian Date: Tue, 19 Oct 2010 14:31:41 +0000 (+0530) Subject: ath9k_hw: Fix divide by zero cases in paprd. X-Git-Tag: firefly_0821_release~7613^2~3176^2~7^2~93 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=2d3fca180710c6832de22c44155ce6a3a4953c6b;p=firefly-linux-kernel-4.4.55.git ath9k_hw: Fix divide by zero cases in paprd. We are not handling all divide by zero cases in paprd. Add additional checks for divide by zero cases in papard. This patch has fixes intended for kernel 2.6.36. Cc: stable@kernel.org Signed-off-by: Senthil Balasubramanian Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/ath/ath9k/ar9003_paprd.c b/drivers/net/wireless/ath/ath9k/ar9003_paprd.c index 7c38229ba670..716db414c258 100644 --- a/drivers/net/wireless/ath/ath9k/ar9003_paprd.c +++ b/drivers/net/wireless/ath/ath9k/ar9003_paprd.c @@ -347,6 +347,10 @@ static bool create_pa_curve(u32 *data_L, u32 *data_U, u32 *pa_table, u16 *gain) (((Y[6] - Y[3]) * 1 << scale_factor) + (x_est[6] - x_est[3])) / (x_est[6] - x_est[3]); + /* prevent division by zero */ + if (G_fxp == 0) + return false; + Y_intercept = (G_fxp * (x_est[0] - x_est[3]) + (1 << scale_factor)) / (1 << scale_factor) + Y[3]; @@ -356,14 +360,12 @@ static bool create_pa_curve(u32 *data_L, u32 *data_U, u32 *pa_table, u16 *gain) for (i = 0; i <= 3; i++) { y_est[i] = i * 32; - - /* prevent division by zero */ - if (G_fxp == 0) - return false; - x_est[i] = ((y_est[i] * 1 << scale_factor) + G_fxp) / G_fxp; } + if (y_est[max_index] == 0) + return false; + x_est_fxp1_nonlin = x_est[max_index] - ((1 << scale_factor) * y_est[max_index] + G_fxp) / G_fxp; @@ -457,6 +459,8 @@ static bool create_pa_curve(u32 *data_L, u32 *data_U, u32 *pa_table, u16 *gain) Q_scale_B = find_proper_scale(find_expn(abs(scale_B)), 10); scale_B = scale_B / (1 << Q_scale_B); + if (scale_B == 0) + return false; Q_beta = find_proper_scale(find_expn(abs(beta_raw)), 10); Q_alpha = find_proper_scale(find_expn(abs(alpha_raw)), 10); beta_raw = beta_raw / (1 << Q_beta);